update GDAS and SETN

README.md

@@ -65,7 +65,10 @@ CUDA_VISIBLE_DEVICES=0 bash ./scripts/nas-infer-train.sh cifar100 SETN 96 -1
 CUDA_VISIBLE_DEVICES=0,1,2,3 bash ./scripts/nas-infer-train.sh imagenet-1k SETN  256 -1
 ```
 
-Searching codes come soon!
+The searching codes of SETN on a small search space:
+```
+CUDA_VISIBLE_DEVICES=0 bash ./scripts-search/algos/SETN.sh cifar10 -1
+```
 
 
 ## [Searching for A Robust Neural Architecture in Four GPU Hours](https://arxiv.org/abs/1910.04465)
@@ -88,7 +91,16 @@ CUDA_VISIBLE_DEVICES=0 bash ./scripts/nas-infer-train.sh cifar100 GDAS_V1 96 -1
 CUDA_VISIBLE_DEVICES=0,1,2,3 bash ./scripts/nas-infer-train.sh imagenet-1k GDAS_V1 256 -1
 ```
 
-Searching codes come soon! A small example forward code segment for searching can be found in [this issue](https://github.com/D-X-Y/NAS-Projects/issues/12).
+The GDAS searching codes on a small search space:
+```
+CUDA_VISIBLE_DEVICES=0 bash ./scripts-search/algos/GDAS.sh cifar10 -1
+```
+
+The baseline searching codes are DARTS:
+```
+CUDA_VISIBLE_DEVICES=0 bash ./scripts-search/algos/DARTS-V1.sh cifar10 -1
+CUDA_VISIBLE_DEVICES=0 bash ./scripts-search/algos/DARTS-V2.sh cifar10 -1
+```
 
 
 ## [Auto-ReID: Searching for a Part-Aware ConvNet for Person Re-Identification](https://arxiv.org/abs/1903.09776)

configs/nas-benchmark/CIFAR.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.0"],
+  "epochs"   : ["int",   "200"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.1"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int", "256"]
+}

configs/nas-benchmark/ImageNet-16.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.0"],
+  "epochs"   : ["int",   "200"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.1"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int", "256"]
+}

configs/nas-benchmark/algos/DARTS.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "50"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

configs/nas-benchmark/algos/GDAS-noacc.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "50"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

configs/nas-benchmark/algos/GDAS.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "240"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

configs/nas-benchmark/algos/R-EA.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "25"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

configs/nas-benchmark/algos/RANDOM.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "150"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

configs/nas-benchmark/algos/SETN.config

@@ -0,0 +1,13 @@
+{
+  "scheduler": ["str",   "cos"],
+  "eta_min"  : ["float", "0.001"],
+  "epochs"   : ["int",   "400"],
+  "warmup"   : ["int",   "0"],
+  "optim"    : ["str",   "SGD"],
+  "LR"       : ["float", "0.025"],
+  "decay"    : ["float", "0.0005"],
+  "momentum" : ["float", "0.9"],
+  "nesterov" : ["bool",  "1"],
+  "criterion": ["str",   "Softmax"],
+  "batch_size": ["int",  "64"]
+}

exps/algos/DARTS-V1.py

@@ -0,0 +1,252 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+##################################################
+import os, sys, time, glob, random, argparse
+import numpy as np
+from copy import deepcopy
+import torch
+import torch.nn as nn
+from pathlib import Path
+lib_dir = (Path(__file__).parent / '..' / '..' / 'lib').resolve()
+if str(lib_dir) not in sys.path: sys.path.insert(0, str(lib_dir))
+from config_utils import load_config, dict2config, configure2str
+from datasets     import get_datasets, SearchDataset
+from procedures   import prepare_seed, prepare_logger, save_checkpoint, copy_checkpoint, get_optim_scheduler
+from utils        import get_model_infos, obtain_accuracy
+from log_utils    import AverageMeter, time_string, convert_secs2time
+from models       import get_cell_based_tiny_net, get_search_spaces
+
+
+def search_func(xloader, network, criterion, scheduler, w_optimizer, a_optimizer, epoch_str, print_freq, logger):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  base_losses, base_top1, base_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.train()
+  end = time.time()
+  for step, (base_inputs, base_targets, arch_inputs, arch_targets) in enumerate(xloader):
+    scheduler.update(None, 1.0 * step / len(xloader))
+    base_targets = base_targets.cuda(non_blocking=True)
+    arch_targets = arch_targets.cuda(non_blocking=True)
+    # measure data loading time
+    data_time.update(time.time() - end)
+    
+    # update the weights
+    w_optimizer.zero_grad()
+    _, logits = network(base_inputs)
+    base_loss = criterion(logits, base_targets)
+    base_loss.backward()
+    torch.nn.utils.clip_grad_norm_(network.parameters(), 5)
+    w_optimizer.step()
+    # record
+    base_prec1, base_prec5 = obtain_accuracy(logits.data, base_targets.data, topk=(1, 5))
+    base_losses.update(base_loss.item(),  base_inputs.size(0))
+    base_top1.update  (base_prec1.item(), base_inputs.size(0))
+    base_top5.update  (base_prec5.item(), base_inputs.size(0))
+
+    # update the architecture-weight
+    a_optimizer.zero_grad()
+    _, logits = network(arch_inputs)
+    arch_loss = criterion(logits, arch_targets)
+    arch_loss.backward()
+    a_optimizer.step()
+    # record
+    arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+    arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+    arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+    arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+
+    # measure elapsed time
+    batch_time.update(time.time() - end)
+    end = time.time()
+
+    if step % print_freq == 0 or step + 1 == len(xloader):
+      Sstr = '*SEARCH* ' + time_string() + ' [{:}][{:03d}/{:03d}]'.format(epoch_str, step, len(xloader))
+      Tstr = 'Time {batch_time.val:.2f} ({batch_time.avg:.2f}) Data {data_time.val:.2f} ({data_time.avg:.2f})'.format(batch_time=batch_time, data_time=data_time)
+      Wstr = 'Base [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=base_losses, top1=base_top1, top5=base_top5)
+      Astr = 'Arch [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=arch_losses, top1=arch_top1, top5=arch_top5)
+      logger.log(Sstr + ' ' + Tstr + ' ' + Wstr + ' ' + Astr)
+  return base_losses.avg, base_top1.avg, base_top5.avg
+
+
+def valid_func(xloader, network, criterion):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.eval()
+  end = time.time()
+  with torch.no_grad():
+    for step, (arch_inputs, arch_targets) in enumerate(xloader):
+      arch_targets = arch_targets.cuda(non_blocking=True)
+      # measure data loading time
+      data_time.update(time.time() - end)
+      # prediction
+      _, logits = network(arch_inputs)
+      arch_loss = criterion(logits, arch_targets)
+      # record
+      arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+      arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+      arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+      arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+      # measure elapsed time
+      batch_time.update(time.time() - end)
+      end = time.time()
+  return arch_losses.avg, arch_top1.avg, arch_top5.avg
+
+
+def main(xargs):
+  assert torch.cuda.is_available(), 'CUDA is not available.'
+  torch.backends.cudnn.enabled   = True
+  torch.backends.cudnn.benchmark = False
+  torch.backends.cudnn.deterministic = True
+  torch.set_num_threads( xargs.workers )
+  prepare_seed(xargs.rand_seed)
+  logger = prepare_logger(args)
+
+  train_data, valid_data, xshape, class_num = get_datasets(xargs.dataset, xargs.data_path, -1)
+  if xargs.dataset == 'cifar10' or xargs.dataset == 'cifar100':
+    split_Fpath = 'configs/nas-benchmark/cifar-split.txt'
+    cifar_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = cifar_split.train, cifar_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  elif xargs.dataset.startswith('ImageNet16'):
+    split_Fpath = 'configs/nas-benchmark/{:}-split.txt'.format(xargs.dataset)
+    imagenet16_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = imagenet16_split.train, imagenet16_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  else:
+    raise ValueError('invalid dataset : {:}'.format(xargs.dataset))
+  config_path = 'configs/nas-benchmark/algos/DARTS.config'
+  config = load_config(config_path, {'class_num': class_num, 'xshape': xshape}, logger)
+  # To split data
+  train_data_v2 = deepcopy(train_data)
+  train_data_v2.transform = valid_data.transform
+  valid_data    = train_data_v2
+  search_data   = SearchDataset(xargs.dataset, train_data, train_split, valid_split)
+  # data loader
+  search_loader = torch.utils.data.DataLoader(search_data, batch_size=config.batch_size, shuffle=True , num_workers=xargs.workers, pin_memory=True)
+  valid_loader  = torch.utils.data.DataLoader(valid_data, batch_size=config.batch_size, sampler=torch.utils.data.sampler.SubsetRandomSampler(valid_split), num_workers=xargs.workers, pin_memory=True)
+  logger.log('||||||| {:10s} ||||||| Search-Loader-Num={:}, Valid-Loader-Num={:}, batch size={:}'.format(xargs.dataset, len(search_loader), len(valid_loader), config.batch_size))
+  logger.log('||||||| {:10s} ||||||| Config={:}'.format(xargs.dataset, config))
+
+  search_space = get_search_spaces('cell', xargs.search_space_name)
+  model_config = dict2config({'name': 'DARTS-V1', 'C': xargs.channel, 'N': xargs.num_cells,
+                              'max_nodes': xargs.max_nodes, 'num_classes': class_num,
+                              'space'    : search_space}, None)
+  search_model = get_cell_based_tiny_net(model_config)
+  
+  w_optimizer, w_scheduler, criterion = get_optim_scheduler(search_model.get_weights(), config)
+  a_optimizer = torch.optim.Adam(search_model.get_alphas(), lr=xargs.arch_learning_rate, betas=(0.5, 0.999), weight_decay=xargs.arch_weight_decay)
+  logger.log('w-optimizer : {:}'.format(w_optimizer))
+  logger.log('a-optimizer : {:}'.format(a_optimizer))
+  logger.log('w-scheduler : {:}'.format(w_scheduler))
+  logger.log('criterion   : {:}'.format(criterion))
+  flop, param  = get_model_infos(search_model, xshape)
+  #logger.log('{:}'.format(search_model))
+  logger.log('FLOP = {:.2f} M, Params = {:.2f} MB'.format(flop, param))
+
+  last_info, model_base_path, model_best_path = logger.path('info'), logger.path('model'), logger.path('best')
+  network, criterion = torch.nn.DataParallel(search_model).cuda(), criterion.cuda()
+
+  if last_info.exists(): # automatically resume from previous checkpoint
+    logger.log("=> loading checkpoint of the last-info '{:}' start".format(last_info))
+    last_info   = torch.load(last_info)
+    start_epoch = last_info['epoch']
+    checkpoint  = torch.load(last_info['last_checkpoint'])
+    genotypes   = checkpoint['genotypes']
+    valid_accuracies = checkpoint['valid_accuracies']
+    search_model.load_state_dict( checkpoint['search_model'] )
+    w_scheduler.load_state_dict ( checkpoint['w_scheduler'] )
+    w_optimizer.load_state_dict ( checkpoint['w_optimizer'] )
+    a_optimizer.load_state_dict ( checkpoint['a_optimizer'] )
+    logger.log("=> loading checkpoint of the last-info '{:}' start with {:}-th epoch.".format(last_info, start_epoch))
+  else:
+    logger.log("=> do not find the last-info file : {:}".format(last_info))
+    start_epoch, valid_accuracies, genotypes = 0, {'best': -1}, {}
+
+  # start training
+  start_time, epoch_time, total_epoch = time.time(), AverageMeter(), config.epochs + config.warmup
+  for epoch in range(start_epoch, total_epoch):
+    w_scheduler.update(epoch, 0.0)
+    need_time = 'Time Left: {:}'.format( convert_secs2time(epoch_time.val * (total_epoch-epoch), True) )
+    epoch_str = '{:03d}-{:03d}'.format(epoch, total_epoch)
+    logger.log('\n[Search the {:}-th epoch] {:}, LR={:}'.format(epoch_str, need_time, min(w_scheduler.get_lr())))
+
+    search_w_loss, search_w_top1, search_w_top5 = search_func(search_loader, network, criterion, w_scheduler, w_optimizer, a_optimizer, epoch_str, xargs.print_freq, logger)
+    logger.log('[{:}] searching : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, search_w_loss, search_w_top1, search_w_top5))
+    valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('[{:}] evaluate  : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss, valid_a_top1, valid_a_top5))
+    # check the best accuracy
+    valid_accuracies[epoch] = valid_a_top1
+    if valid_a_top1 > valid_accuracies['best']:
+      valid_accuracies['best'] = valid_a_top1
+      genotypes['best']        = search_model.genotype()
+      find_best = True
+    else: find_best = False
+
+    genotypes[epoch] = search_model.genotype()
+    logger.log('<<<--->>> The {:}-th epoch : {:}'.format(epoch_str, genotypes[epoch]))
+    # save checkpoint
+    save_path = save_checkpoint({'epoch' : epoch + 1,
+                'args'  : deepcopy(xargs),
+                'search_model': search_model.state_dict(),
+                'w_optimizer' : w_optimizer.state_dict(),
+                'a_optimizer' : a_optimizer.state_dict(),
+                'w_scheduler' : w_scheduler.state_dict(),
+                'genotypes'   : genotypes,
+                'valid_accuracies' : valid_accuracies},
+                model_base_path, logger)
+    last_info = save_checkpoint({
+          'epoch': epoch + 1,
+          'args' : deepcopy(args),
+          'last_checkpoint': save_path,
+          }, logger.path('info'), logger)
+    if find_best:
+      logger.log('<<<--->>> The {:}-th epoch : find the highest validation accuracy : {:.2f}%.'.format(epoch_str, valid_a_top1))
+      copy_checkpoint(model_base_path, model_best_path, logger)
+    with torch.no_grad():
+      logger.log('arch-parameters :\n{:}'.format( nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu() ))
+    # measure elapsed time
+    epoch_time.update(time.time() - start_time)
+    start_time = time.time()
+
+  logger.log('\n' + '-'*100)
+  # check the performance from the architecture dataset
+  #if xargs.arch_nas_dataset is None or not os.path.isfile(xargs.arch_nas_dataset):
+  #  logger.log('Can not find the architecture dataset : {:}.'.format(xargs.arch_nas_dataset))
+  #else:
+  #  nas_bench = NASBenchmarkAPI(xargs.arch_nas_dataset)
+  #  geno = genotypes[total_epoch-1]
+  #  logger.log('The last model is {:}'.format(geno))
+  #  info = nas_bench.query_by_arch( geno )
+  #  if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+  #  else           : logger.log('{:}'.format(info))
+  #  logger.log('-'*100)
+  #  geno = genotypes['best']
+  #  logger.log('The best model is {:}'.format(geno))
+  #  info = nas_bench.query_by_arch( geno )
+  #  if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+  #  else           : logger.log('{:}'.format(info))
+  logger.close()
+  
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser("DARTS first order")
+  parser.add_argument('--data_path',          type=str,   help='Path to dataset')
+  parser.add_argument('--dataset',            type=str,   choices=['cifar10', 'cifar100', 'ImageNet16-120'], help='Choose between Cifar10/100 and ImageNet-16.')
+  # channels and number-of-cells
+  parser.add_argument('--search_space_name',  type=str,   help='The search space name.')
+  parser.add_argument('--max_nodes',          type=int,   help='The maximum number of nodes.')
+  parser.add_argument('--channel',            type=int,   help='The number of channels.')
+  parser.add_argument('--num_cells',          type=int,   help='The number of cells in one stage.')
+  # architecture leraning rate
+  parser.add_argument('--arch_learning_rate', type=float, default=3e-4, help='learning rate for arch encoding')
+  parser.add_argument('--arch_weight_decay',  type=float, default=1e-3, help='weight decay for arch encoding')
+  # log
+  parser.add_argument('--workers',            type=int,   default=2,    help='number of data loading workers (default: 2)')
+  parser.add_argument('--save_dir',           type=str,   help='Folder to save checkpoints and log.')
+  parser.add_argument('--arch_nas_dataset',   type=str,   help='The path to load the architecture dataset (nas-benchmark).')
+  parser.add_argument('--print_freq',         type=int,   help='print frequency (default: 200)')
+  parser.add_argument('--rand_seed',          type=int,   help='manual seed')
+  args = parser.parse_args()
+  if args.rand_seed is None or args.rand_seed < 0: args.rand_seed = random.randint(1, 100000)
+  main(args)

exps/algos/DARTS-V2.py

@@ -0,0 +1,319 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+##################################################
+import os, sys, time, glob, random, argparse
+import numpy as np
+from copy import deepcopy
+import torch
+import torch.nn as nn
+from pathlib import Path
+lib_dir = (Path(__file__).parent / '..' / '..' / 'lib').resolve()
+if str(lib_dir) not in sys.path: sys.path.insert(0, str(lib_dir))
+from config_utils import load_config, dict2config, configure2str
+from datasets     import get_datasets, SearchDataset
+from procedures   import prepare_seed, prepare_logger, save_checkpoint, copy_checkpoint, get_optim_scheduler
+from utils        import get_model_infos, obtain_accuracy
+from log_utils    import AverageMeter, time_string, convert_secs2time
+from models       import get_cell_based_tiny_net, get_search_spaces
+
+
+def _concat(xs):
+  return torch.cat([x.view(-1) for x in xs])
+
+
+def _hessian_vector_product(vector, network, criterion, base_inputs, base_targets, r=1e-2):
+  R = r / _concat(vector).norm()
+  for p, v in zip(network.module.get_weights(), vector):
+    p.data.add_(R, v)
+  _, logits = network(base_inputs)
+  loss = criterion(logits, base_targets)
+  grads_p = torch.autograd.grad(loss, network.module.get_alphas())
+
+  for p, v in zip(network.module.get_weights(), vector):
+    p.data.sub_(2*R, v)
+  _, logits = network(base_inputs)
+  loss = criterion(logits, base_targets)
+  grads_n = torch.autograd.grad(loss, network.module.get_alphas())
+
+  for p, v in zip(network.module.get_weights(), vector):
+    p.data.add_(R, v)
+  return [(x-y).div_(2*R) for x, y in zip(grads_p, grads_n)]
+
+
+def backward_step_unrolled(network, criterion, base_inputs, base_targets, w_optimizer, arch_inputs, arch_targets):
+  # _compute_unrolled_model
+  _, logits = network(base_inputs)
+  loss = criterion(logits, base_targets)
+  LR, WD, momentum = w_optimizer.param_groups[0]['lr'], w_optimizer.param_groups[0]['weight_decay'], w_optimizer.param_groups[0]['momentum']
+  with torch.no_grad():
+    theta = _concat(network.module.get_weights())
+    try:
+      moment = _concat(w_optimizer.state[v]['momentum_buffer'] for v in network.module.get_weights())
+      moment = moment.mul_(momentum)
+    except:
+      moment = torch.zeros_like(theta)
+    dtheta = _concat(torch.autograd.grad(loss, network.module.get_weights())) + WD*theta
+    params = theta.sub(LR, moment+dtheta)
+  unrolled_model = deepcopy(network)
+  model_dict  = unrolled_model.state_dict()
+  new_params, offset = {}, 0
+  for k, v in network.named_parameters():
+    if 'arch_parameters' in k: continue
+    v_length = np.prod(v.size())
+    new_params[k] = params[offset: offset+v_length].view(v.size())
+    offset += v_length
+  model_dict.update(new_params)
+  unrolled_model.load_state_dict(model_dict)
+
+  unrolled_model.zero_grad()
+  _, unrolled_logits = unrolled_model(arch_inputs)
+  unrolled_loss = criterion(unrolled_logits, arch_targets)
+  unrolled_loss.backward()
+
+  dalpha = unrolled_model.module.arch_parameters.grad
+  vector = [v.grad.data for v in unrolled_model.module.get_weights()]
+  [implicit_grads] = _hessian_vector_product(vector, network, criterion, base_inputs, base_targets)
+  
+  dalpha.data.sub_(LR, implicit_grads.data)
+
+  if network.module.arch_parameters.grad is None:
+    network.module.arch_parameters.grad = deepcopy( dalpha )
+  else:
+    network.module.arch_parameters.grad.data.copy_( dalpha.data )
+  return unrolled_loss.detach(), unrolled_logits.detach()
+  
+
+def search_func(xloader, network, criterion, scheduler, w_optimizer, a_optimizer, epoch_str, print_freq, logger):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  base_losses, base_top1, base_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.train()
+  end = time.time()
+  for step, (base_inputs, base_targets, arch_inputs, arch_targets) in enumerate(xloader):
+    scheduler.update(None, 1.0 * step / len(xloader))
+    base_targets = base_targets.cuda(non_blocking=True)
+    arch_targets = arch_targets.cuda(non_blocking=True)
+    # measure data loading time
+    data_time.update(time.time() - end)
+
+    # update the architecture-weight
+    a_optimizer.zero_grad()
+    arch_loss, arch_logits = backward_step_unrolled(network, criterion, base_inputs, base_targets, w_optimizer, arch_inputs, arch_targets)
+    a_optimizer.step()
+    # record
+    arch_prec1, arch_prec5 = obtain_accuracy(arch_logits.data, arch_targets.data, topk=(1, 5))
+    arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+    arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+    arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+    
+    # update the weights
+    w_optimizer.zero_grad()
+    _, logits = network(base_inputs)
+    base_loss = criterion(logits, base_targets)
+    base_loss.backward()
+    torch.nn.utils.clip_grad_norm_(network.parameters(), 5)
+    w_optimizer.step()
+    # record
+    base_prec1, base_prec5 = obtain_accuracy(logits.data, base_targets.data, topk=(1, 5))
+    base_losses.update(base_loss.item(),  base_inputs.size(0))
+    base_top1.update  (base_prec1.item(), base_inputs.size(0))
+    base_top5.update  (base_prec5.item(), base_inputs.size(0))
+
+    # measure elapsed time
+    batch_time.update(time.time() - end)
+    end = time.time()
+
+    if step % print_freq == 0 or step + 1 == len(xloader):
+      Sstr = '*SEARCH* ' + time_string() + ' [{:}][{:03d}/{:03d}]'.format(epoch_str, step, len(xloader))
+      Tstr = 'Time {batch_time.val:.2f} ({batch_time.avg:.2f}) Data {data_time.val:.2f} ({data_time.avg:.2f})'.format(batch_time=batch_time, data_time=data_time)
+      Wstr = 'Base [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=base_losses, top1=base_top1, top5=base_top5)
+      Astr = 'Arch [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=arch_losses, top1=arch_top1, top5=arch_top5)
+      logger.log(Sstr + ' ' + Tstr + ' ' + Wstr + ' ' + Astr)
+  return base_losses.avg, base_top1.avg, base_top5.avg
+
+
+def valid_func(xloader, network, criterion):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.eval()
+  end = time.time()
+  with torch.no_grad():
+    for step, (arch_inputs, arch_targets) in enumerate(xloader):
+      arch_targets = arch_targets.cuda(non_blocking=True)
+      # measure data loading time
+      data_time.update(time.time() - end)
+      # prediction
+      _, logits = network(arch_inputs)
+      arch_loss = criterion(logits, arch_targets)
+      # record
+      arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+      arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+      arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+      arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+      # measure elapsed time
+      batch_time.update(time.time() - end)
+      end = time.time()
+  return arch_losses.avg, arch_top1.avg, arch_top5.avg
+
+
+def main(xargs):
+  assert torch.cuda.is_available(), 'CUDA is not available.'
+  torch.backends.cudnn.enabled   = True
+  torch.backends.cudnn.benchmark = False
+  torch.backends.cudnn.deterministic = True
+  torch.set_num_threads( xargs.workers )
+  prepare_seed(xargs.rand_seed)
+  logger = prepare_logger(args)
+
+  train_data, valid_data, xshape, class_num = get_datasets(xargs.dataset, xargs.data_path, -1)
+  if xargs.dataset == 'cifar10' or xargs.dataset == 'cifar100':
+    split_Fpath = 'configs/nas-benchmark/cifar-split.txt'
+    cifar_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = cifar_split.train, cifar_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  elif xargs.dataset.startswith('ImageNet16'):
+    split_Fpath = 'configs/nas-benchmark/{:}-split.txt'.format(xargs.dataset)
+    imagenet16_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = imagenet16_split.train, imagenet16_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  else:
+    raise ValueError('invalid dataset : {:}'.format(xargs.dataset))
+  config_path = 'configs/nas-benchmark/algos/DARTS.config'
+  config = load_config(config_path, {'class_num': class_num, 'xshape': xshape}, logger)
+  # To split data
+  train_data_v2 = deepcopy(train_data)
+  train_data_v2.transform = valid_data.transform
+  valid_data    = train_data_v2
+  search_data   = SearchDataset(xargs.dataset, train_data, train_split, valid_split)
+  # data loader
+  search_loader = torch.utils.data.DataLoader(search_data, batch_size=config.batch_size, shuffle=True , num_workers=xargs.workers, pin_memory=True)
+  valid_loader  = torch.utils.data.DataLoader(valid_data, batch_size=config.batch_size, sampler=torch.utils.data.sampler.SubsetRandomSampler(valid_split), num_workers=xargs.workers, pin_memory=True)
+  logger.log('||||||| {:10s} ||||||| Search-Loader-Num={:}, Valid-Loader-Num={:}, batch size={:}'.format(xargs.dataset, len(search_loader), len(valid_loader), config.batch_size))
+  logger.log('||||||| {:10s} ||||||| Config={:}'.format(xargs.dataset, config))
+
+  search_space = get_search_spaces('cell', xargs.search_space_name)
+  model_config = dict2config({'name': 'DARTS-V2', 'C': xargs.channel, 'N': xargs.num_cells,
+                              'max_nodes': xargs.max_nodes, 'num_classes': class_num,
+                              'space'    : search_space}, None)
+  search_model = get_cell_based_tiny_net(model_config)
+  
+  w_optimizer, w_scheduler, criterion = get_optim_scheduler(search_model.get_weights(), config)
+  a_optimizer = torch.optim.Adam(search_model.get_alphas(), lr=xargs.arch_learning_rate, betas=(0.5, 0.999), weight_decay=xargs.arch_weight_decay)
+  logger.log('w-optimizer : {:}'.format(w_optimizer))
+  logger.log('a-optimizer : {:}'.format(a_optimizer))
+  logger.log('w-scheduler : {:}'.format(w_scheduler))
+  logger.log('criterion   : {:}'.format(criterion))
+  flop, param  = get_model_infos(search_model, xshape)
+  #logger.log('{:}'.format(search_model))
+  logger.log('FLOP = {:.2f} M, Params = {:.2f} MB'.format(flop, param))
+
+  last_info, model_base_path, model_best_path = logger.path('info'), logger.path('model'), logger.path('best')
+  network, criterion = torch.nn.DataParallel(search_model).cuda(), criterion.cuda()
+
+  if last_info.exists(): # automatically resume from previous checkpoint
+    logger.log("=> loading checkpoint of the last-info '{:}' start".format(last_info))
+    last_info   = torch.load(last_info)
+    start_epoch = last_info['epoch']
+    checkpoint  = torch.load(last_info['last_checkpoint'])
+    genotypes   = checkpoint['genotypes']
+    valid_accuracies = checkpoint['valid_accuracies']
+    search_model.load_state_dict( checkpoint['search_model'] )
+    w_scheduler.load_state_dict ( checkpoint['w_scheduler'] )
+    w_optimizer.load_state_dict ( checkpoint['w_optimizer'] )
+    a_optimizer.load_state_dict ( checkpoint['a_optimizer'] )
+    logger.log("=> loading checkpoint of the last-info '{:}' start with {:}-th epoch.".format(last_info, start_epoch))
+  else:
+    logger.log("=> do not find the last-info file : {:}".format(last_info))
+    start_epoch, valid_accuracies, genotypes = 0, {'best': -1}, {}
+
+  # start training
+  start_time, epoch_time, total_epoch = time.time(), AverageMeter(), config.epochs + config.warmup
+  for epoch in range(start_epoch, total_epoch):
+    w_scheduler.update(epoch, 0.0)
+    need_time = 'Time Left: {:}'.format( convert_secs2time(epoch_time.val * (total_epoch-epoch), True) )
+    epoch_str = '{:03d}-{:03d}'.format(epoch, total_epoch)
+    min_LR    = min(w_scheduler.get_lr())
+    logger.log('\n[Search the {:}-th epoch] {:}, LR={:}'.format(epoch_str, need_time, min_LR))
+
+    search_w_loss, search_w_top1, search_w_top5 = search_func(search_loader, network, criterion, w_scheduler, w_optimizer, a_optimizer, epoch_str, xargs.print_freq, logger)
+    logger.log('[{:}] searching : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, search_w_loss, search_w_top1, search_w_top5))
+    valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('[{:}] evaluate  : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss, valid_a_top1, valid_a_top5))
+    # check the best accuracy
+    valid_accuracies[epoch] = valid_a_top1
+    if valid_a_top1 > valid_accuracies['best']:
+      valid_accuracies['best'] = valid_a_top1
+      genotypes['best']        = search_model.genotype()
+      find_best = True
+    else: find_best = False
+
+    genotypes[epoch] = search_model.genotype()
+    logger.log('<<<--->>> The {:}-th epoch : {:}'.format(epoch_str, genotypes[epoch]))
+    # save checkpoint
+    save_path = save_checkpoint({'epoch' : epoch + 1,
+                'args'  : deepcopy(xargs),
+                'search_model': search_model.state_dict(),
+                'w_optimizer' : w_optimizer.state_dict(),
+                'a_optimizer' : a_optimizer.state_dict(),
+                'w_scheduler' : w_scheduler.state_dict(),
+                'genotypes'   : genotypes,
+                'valid_accuracies' : valid_accuracies},
+                model_base_path, logger)
+    last_info = save_checkpoint({
+          'epoch': epoch + 1,
+          'args' : deepcopy(args),
+          'last_checkpoint': save_path,
+          }, logger.path('info'), logger)
+    if find_best:
+      logger.log('<<<--->>> The {:}-th epoch : find the highest validation accuracy : {:.2f}%.'.format(epoch_str, valid_a_top1))
+      copy_checkpoint(model_base_path, model_best_path, logger)
+    with torch.no_grad():
+      logger.log('arch-parameters :\n{:}'.format( nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu() ))
+    # measure elapsed time
+    epoch_time.update(time.time() - start_time)
+    start_time = time.time()
+
+  logger.log('\n' + '-'*100)
+  # check the performance from the architecture dataset
+  """
+  if xargs.arch_nas_dataset is None or not os.path.isfile(xargs.arch_nas_dataset):
+    logger.log('Can not find the architecture dataset : {:}.'.format(xargs.arch_nas_dataset))
+  else:
+    nas_bench = NASBenchmarkAPI(xargs.arch_nas_dataset)
+    geno = genotypes[total_epoch-1]
+    logger.log('The last model is {:}'.format(geno))
+    info = nas_bench.query_by_arch( geno )
+    if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+    else           : logger.log('{:}'.format(info))
+    logger.log('-'*100)
+    geno = genotypes['best']
+    logger.log('The best model is {:}'.format(geno))
+    info = nas_bench.query_by_arch( geno )
+    if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+    else           : logger.log('{:}'.format(info))
+  """
+  logger.close()
+  
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser("DARTS Second Order")
+  parser.add_argument('--data_path',          type=str,   help='Path to dataset')
+  parser.add_argument('--dataset',            type=str,   choices=['cifar10', 'cifar100', 'ImageNet16-120'], help='Choose between Cifar10/100 and ImageNet-16.')
+  # channels and number-of-cells
+  parser.add_argument('--search_space_name',  type=str,   help='The search space name.')
+  parser.add_argument('--max_nodes',          type=int,   help='The maximum number of nodes.')
+  parser.add_argument('--channel',            type=int,   help='The number of channels.')
+  parser.add_argument('--num_cells',          type=int,   help='The number of cells in one stage.')
+  # architecture leraning rate
+  parser.add_argument('--arch_learning_rate', type=float, default=3e-4, help='learning rate for arch encoding')
+  parser.add_argument('--arch_weight_decay',  type=float, default=1e-3, help='weight decay for arch encoding')
+  # log
+  parser.add_argument('--workers',            type=int,   default=2,    help='number of data loading workers (default: 2)')
+  parser.add_argument('--save_dir',           type=str,   help='Folder to save checkpoints and log.')
+  parser.add_argument('--arch_nas_dataset',   type=str,   help='The path to load the architecture dataset (tiny-nas-benchmark).')
+  parser.add_argument('--print_freq',         type=int,   help='print frequency (default: 200)')
+  parser.add_argument('--rand_seed',          type=int,   help='manual seed')
+  args = parser.parse_args()
+  if args.rand_seed is None or args.rand_seed < 0: args.rand_seed = random.randint(1, 100000)
+  main(args)

exps/algos/GDAS.py

@@ -0,0 +1,224 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+##################################################
+import os, sys, time, glob, random, argparse
+import numpy as np
+from copy import deepcopy
+import torch
+import torch.nn as nn
+from pathlib import Path
+lib_dir = (Path(__file__).parent / '..' / '..' / 'lib').resolve()
+if str(lib_dir) not in sys.path: sys.path.insert(0, str(lib_dir))
+from config_utils import load_config, dict2config, configure2str
+from datasets     import get_datasets, SearchDataset
+from procedures   import prepare_seed, prepare_logger, save_checkpoint, copy_checkpoint, get_optim_scheduler
+from utils        import get_model_infos, obtain_accuracy
+from log_utils    import AverageMeter, time_string, convert_secs2time
+from models       import get_cell_based_tiny_net, get_search_spaces
+
+
+def search_func(xloader, network, criterion, scheduler, w_optimizer, a_optimizer, epoch_str, print_freq, logger):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  base_losses, base_top1, base_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.train()
+  end = time.time()
+  for step, (base_inputs, base_targets, arch_inputs, arch_targets) in enumerate(xloader):
+    scheduler.update(None, 1.0 * step / len(xloader))
+    base_targets = base_targets.cuda(non_blocking=True)
+    arch_targets = arch_targets.cuda(non_blocking=True)
+    # measure data loading time
+    data_time.update(time.time() - end)
+    
+    # update the weights
+    w_optimizer.zero_grad()
+    _, logits = network(base_inputs)
+    base_loss = criterion(logits, base_targets)
+    base_loss.backward()
+    torch.nn.utils.clip_grad_norm_(network.parameters(), 5)
+    w_optimizer.step()
+    # record
+    base_prec1, base_prec5 = obtain_accuracy(logits.data, base_targets.data, topk=(1, 5))
+    base_losses.update(base_loss.item(),  base_inputs.size(0))
+    base_top1.update  (base_prec1.item(), base_inputs.size(0))
+    base_top5.update  (base_prec5.item(), base_inputs.size(0))
+
+    # update the architecture-weight
+    a_optimizer.zero_grad()
+    _, logits = network(arch_inputs)
+    arch_loss = criterion(logits, arch_targets)
+    arch_loss.backward()
+    a_optimizer.step()
+    # record
+    arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+    arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+    arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+    arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+
+    # measure elapsed time
+    batch_time.update(time.time() - end)
+    end = time.time()
+
+    if step % print_freq == 0 or step + 1 == len(xloader):
+      Sstr = '*SEARCH* ' + time_string() + ' [{:}][{:03d}/{:03d}]'.format(epoch_str, step, len(xloader))
+      Tstr = 'Time {batch_time.val:.2f} ({batch_time.avg:.2f}) Data {data_time.val:.2f} ({data_time.avg:.2f})'.format(batch_time=batch_time, data_time=data_time)
+      Wstr = 'Base [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=base_losses, top1=base_top1, top5=base_top5)
+      Astr = 'Arch [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=arch_losses, top1=arch_top1, top5=arch_top5)
+      logger.log(Sstr + ' ' + Tstr + ' ' + Wstr + ' ' + Astr)
+  return base_losses.avg, base_top1.avg, base_top5.avg, arch_losses.avg, arch_top1.avg, arch_top5.avg
+
+
+def main(xargs):
+  assert torch.cuda.is_available(), 'CUDA is not available.'
+  torch.backends.cudnn.enabled   = True
+  torch.backends.cudnn.benchmark = False
+  torch.backends.cudnn.deterministic = True
+  torch.set_num_threads( xargs.workers )
+  prepare_seed(xargs.rand_seed)
+  logger = prepare_logger(args)
+
+  train_data, _, xshape, class_num = get_datasets(xargs.dataset, xargs.data_path, -1)
+  if xargs.dataset == 'cifar10' or xargs.dataset == 'cifar100':
+    split_Fpath = 'configs/nas-benchmark/cifar-split.txt'
+    cifar_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = cifar_split.train, cifar_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  elif xargs.dataset.startswith('ImageNet16'):
+    split_Fpath = 'configs/nas-benchmark/{:}-split.txt'.format(xargs.dataset)
+    imagenet16_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = imagenet16_split.train, imagenet16_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  else:
+    raise ValueError('invalid dataset : {:}'.format(xargs.dataset))
+  config_path = 'configs/nas-benchmark/algos/GDAS.config'
+  config = load_config(config_path, {'class_num': class_num, 'xshape': xshape}, logger)
+  search_data   = SearchDataset(xargs.dataset, train_data, train_split, valid_split)
+  # data loader
+  search_loader = torch.utils.data.DataLoader(search_data, batch_size=config.batch_size, shuffle=True , num_workers=xargs.workers, pin_memory=True)
+  logger.log('||||||| {:10s} ||||||| Search-Loader-Num={:}, batch size={:}'.format(xargs.dataset, len(search_loader), config.batch_size))
+  logger.log('||||||| {:10s} ||||||| Config={:}'.format(xargs.dataset, config))
+
+  search_space = get_search_spaces('cell', xargs.search_space_name)
+  model_config = dict2config({'name': 'GDAS', 'C': xargs.channel, 'N': xargs.num_cells,
+                              'max_nodes': xargs.max_nodes, 'num_classes': class_num,
+                              'space'    : search_space}, None)
+  search_model = get_cell_based_tiny_net(model_config)
+  
+  w_optimizer, w_scheduler, criterion = get_optim_scheduler(search_model.get_weights(), config)
+  a_optimizer = torch.optim.Adam(search_model.get_alphas(), lr=xargs.arch_learning_rate, betas=(0.5, 0.999), weight_decay=xargs.arch_weight_decay)
+  logger.log('w-optimizer : {:}'.format(w_optimizer))
+  logger.log('a-optimizer : {:}'.format(a_optimizer))
+  logger.log('w-scheduler : {:}'.format(w_scheduler))
+  logger.log('criterion   : {:}'.format(criterion))
+  flop, param  = get_model_infos(search_model, xshape)
+  #logger.log('{:}'.format(search_model))
+  logger.log('FLOP = {:.2f} M, Params = {:.2f} MB'.format(flop, param))
+  logger.log('search_space : {:}'.format(search_space))
+
+  last_info, model_base_path, model_best_path = logger.path('info'), logger.path('model'), logger.path('best')
+  network, criterion = torch.nn.DataParallel(search_model).cuda(), criterion.cuda()
+
+  if last_info.exists(): # automatically resume from previous checkpoint
+    logger.log("=> loading checkpoint of the last-info '{:}' start".format(last_info))
+    last_info   = torch.load(last_info)
+    start_epoch = last_info['epoch']
+    checkpoint  = torch.load(last_info['last_checkpoint'])
+    genotypes   = checkpoint['genotypes']
+    valid_accuracies = checkpoint['valid_accuracies']
+    search_model.load_state_dict( checkpoint['search_model'] )
+    w_scheduler.load_state_dict ( checkpoint['w_scheduler'] )
+    w_optimizer.load_state_dict ( checkpoint['w_optimizer'] )
+    a_optimizer.load_state_dict ( checkpoint['a_optimizer'] )
+    logger.log("=> loading checkpoint of the last-info '{:}' start with {:}-th epoch.".format(last_info, start_epoch))
+  else:
+    logger.log("=> do not find the last-info file : {:}".format(last_info))
+    start_epoch, valid_accuracies, genotypes = 0, {'best': -1}, {}
+
+  # start training
+  start_time, epoch_time, total_epoch = time.time(), AverageMeter(), config.epochs + config.warmup
+  for epoch in range(start_epoch, total_epoch):
+    w_scheduler.update(epoch, 0.0)
+    need_time = 'Time Left: {:}'.format( convert_secs2time(epoch_time.val * (total_epoch-epoch), True) )
+    epoch_str = '{:03d}-{:03d}'.format(epoch, total_epoch)
+    search_model.set_tau( xargs.tau_max - (xargs.tau_max-xargs.tau_min) * epoch / (total_epoch-1) )
+    logger.log('\n[Search the {:}-th epoch] {:}, tau={:}, LR={:}'.format(epoch_str, need_time, search_model.get_tau(), min(w_scheduler.get_lr())))
+
+    search_w_loss, search_w_top1, search_w_top5, valid_a_loss , valid_a_top1 , valid_a_top5 \
+              = search_func(search_loader, network, criterion, w_scheduler, w_optimizer, a_optimizer, epoch_str, xargs.print_freq, logger)
+    logger.log('[{:}] searching : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, search_w_loss, search_w_top1, search_w_top5))
+    logger.log('[{:}] evaluate  : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss , valid_a_top1 , valid_a_top5 ))
+    # check the best accuracy
+    valid_accuracies[epoch] = valid_a_top1
+    if valid_a_top1 > valid_accuracies['best']:
+      valid_accuracies['best'] = valid_a_top1
+      genotypes['best']        = search_model.genotype()
+      find_best = True
+    else: find_best = False
+
+    genotypes[epoch] = search_model.genotype()
+    logger.log('<<<--->>> The {:}-th epoch : {:}'.format(epoch_str, genotypes[epoch]))
+    # save checkpoint
+    save_path = save_checkpoint({'epoch' : epoch + 1,
+                'args'  : deepcopy(xargs),
+                'search_model': search_model.state_dict(),
+                'w_optimizer' : w_optimizer.state_dict(),
+                'a_optimizer' : a_optimizer.state_dict(),
+                'w_scheduler' : w_scheduler.state_dict(),
+                'genotypes'   : genotypes,
+                'valid_accuracies' : valid_accuracies},
+                model_base_path, logger)
+    last_info = save_checkpoint({
+          'epoch': epoch + 1,
+          'args' : deepcopy(args),
+          'last_checkpoint': save_path,
+          }, logger.path('info'), logger)
+    if find_best:
+      logger.log('<<<--->>> The {:}-th epoch : find the highest validation accuracy : {:.2f}%.'.format(epoch_str, valid_a_top1))
+      copy_checkpoint(model_base_path, model_best_path, logger)
+    with torch.no_grad():
+      logger.log('arch-parameters :\n{:}'.format( nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu() ))
+    # measure elapsed time
+    epoch_time.update(time.time() - start_time)
+    start_time = time.time()
+
+  logger.log('\n' + '-'*100)
+  # check the performance from the architecture dataset
+  """
+  if xargs.arch_nas_dataset is None or not os.path.isfile(xargs.arch_nas_dataset):
+    logger.log('Can not find the architecture dataset : {:}.'.format(xargs.arch_nas_dataset))
+  else:
+    nas_bench = NASBenchmarkAPI(xargs.arch_nas_dataset)
+    geno = genotypes[total_epoch-1]
+    logger.log('The last model is {:}'.format(geno))
+    info = nas_bench.query_by_arch( geno )
+    if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+    else           : logger.log('{:}'.format(info))
+    logger.log('-'*100)
+  """
+  logger.close()
+  
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser("GDAS")
+  parser.add_argument('--data_path',          type=str,   help='Path to dataset')
+  parser.add_argument('--dataset',            type=str,   choices=['cifar10', 'cifar100', 'ImageNet16-120'], help='Choose between Cifar10/100 and ImageNet-16.')
+  # channels and number-of-cells
+  parser.add_argument('--search_space_name',  type=str,   help='The search space name.')
+  parser.add_argument('--max_nodes',          type=int,   help='The maximum number of nodes.')
+  parser.add_argument('--channel',            type=int,   help='The number of channels.')
+  parser.add_argument('--num_cells',          type=int,   help='The number of cells in one stage.')
+  # architecture leraning rate
+  parser.add_argument('--arch_learning_rate', type=float, default=3e-4, help='learning rate for arch encoding')
+  parser.add_argument('--arch_weight_decay',  type=float, default=1e-3, help='weight decay for arch encoding')
+  parser.add_argument('--tau_min',            type=float,               help='The minimum tau for Gumbel')
+  parser.add_argument('--tau_max',            type=float,               help='The maximum tau for Gumbel')
+  # log
+  parser.add_argument('--workers',            type=int,   default=2,    help='number of data loading workers (default: 2)')
+  parser.add_argument('--save_dir',           type=str,   help='Folder to save checkpoints and log.')
+  parser.add_argument('--arch_nas_dataset',   type=str,   help='The path to load the architecture dataset (tiny-nas-benchmark).')
+  parser.add_argument('--print_freq',         type=int,   help='print frequency (default: 200)')
+  parser.add_argument('--rand_seed',          type=int,   help='manual seed')
+  args = parser.parse_args()
+  if args.rand_seed is None or args.rand_seed < 0: args.rand_seed = random.randint(1, 100000)
+  main(args)

exps/algos/SETN.py

@@ -0,0 +1,281 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+##################################################
+# One-Shot Neural Architecture Search via Self-Evaluated Template Network, ICCV 2019
+##################################################
+import os, sys, time, glob, random, argparse
+import numpy as np
+from copy import deepcopy
+import torch
+import torch.nn as nn
+from pathlib import Path
+lib_dir = (Path(__file__).parent / '..' / '..' / 'lib').resolve()
+if str(lib_dir) not in sys.path: sys.path.insert(0, str(lib_dir))
+from config_utils import load_config, dict2config, configure2str
+from datasets     import get_datasets, SearchDataset
+from procedures   import prepare_seed, prepare_logger, save_checkpoint, copy_checkpoint, get_optim_scheduler
+from utils        import get_model_infos, obtain_accuracy
+from log_utils    import AverageMeter, time_string, convert_secs2time
+from models       import get_cell_based_tiny_net, get_search_spaces
+
+
+def search_func(xloader, network, criterion, scheduler, w_optimizer, a_optimizer, epoch_str, print_freq, logger):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  base_losses, base_top1, base_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.train()
+  end = time.time()
+  for step, (base_inputs, base_targets, arch_inputs, arch_targets) in enumerate(xloader):
+    scheduler.update(None, 1.0 * step / len(xloader))
+    base_targets = base_targets.cuda(non_blocking=True)
+    arch_targets = arch_targets.cuda(non_blocking=True)
+    # measure data loading time
+    data_time.update(time.time() - end)
+    
+    # update the weights
+    network.module.set_cal_mode( 'urs' )
+    w_optimizer.zero_grad()
+    _, logits = network(base_inputs)
+    base_loss = criterion(logits, base_targets)
+    base_loss.backward()
+    w_optimizer.step()
+    # record
+    base_prec1, base_prec5 = obtain_accuracy(logits.data, base_targets.data, topk=(1, 5))
+    base_losses.update(base_loss.item(),  base_inputs.size(0))
+    base_top1.update  (base_prec1.item(), base_inputs.size(0))
+    base_top5.update  (base_prec5.item(), base_inputs.size(0))
+
+    # update the architecture-weight
+    network.module.set_cal_mode( 'joint' )
+    a_optimizer.zero_grad()
+    _, logits = network(arch_inputs)
+    arch_loss = criterion(logits, arch_targets)
+    arch_loss.backward()
+    a_optimizer.step()
+    # record
+    arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+    arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+    arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+    arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+
+    # measure elapsed time
+    batch_time.update(time.time() - end)
+    end = time.time()
+
+    if step % print_freq == 0 or step + 1 == len(xloader):
+      Sstr = '*SEARCH* ' + time_string() + ' [{:}][{:03d}/{:03d}]'.format(epoch_str, step, len(xloader))
+      Tstr = 'Time {batch_time.val:.2f} ({batch_time.avg:.2f}) Data {data_time.val:.2f} ({data_time.avg:.2f})'.format(batch_time=batch_time, data_time=data_time)
+      Wstr = 'Base [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=base_losses, top1=base_top1, top5=base_top5)
+      Astr = 'Arch [Loss {loss.val:.3f} ({loss.avg:.3f})  Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]'.format(loss=arch_losses, top1=arch_top1, top5=arch_top5)
+      logger.log(Sstr + ' ' + Tstr + ' ' + Wstr + ' ' + Astr)
+  return base_losses.avg, base_top1.avg, base_top5.avg
+
+
+def valid_func(xloader, network, criterion):
+  data_time, batch_time = AverageMeter(), AverageMeter()
+  arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
+  network.train()
+  end = time.time()
+  with torch.no_grad():
+    for step, (arch_inputs, arch_targets) in enumerate(xloader):
+      arch_targets = arch_targets.cuda(non_blocking=True)
+      # measure data loading time
+      data_time.update(time.time() - end)
+      # prediction
+      _, logits = network(arch_inputs)
+      arch_loss = criterion(logits, arch_targets)
+      # record
+      arch_prec1, arch_prec5 = obtain_accuracy(logits.data, arch_targets.data, topk=(1, 5))
+      arch_losses.update(arch_loss.item(),  arch_inputs.size(0))
+      arch_top1.update  (arch_prec1.item(), arch_inputs.size(0))
+      arch_top5.update  (arch_prec5.item(), arch_inputs.size(0))
+      # measure elapsed time
+      batch_time.update(time.time() - end)
+      end = time.time()
+  return arch_losses.avg, arch_top1.avg, arch_top5.avg
+
+
+def main(xargs):
+  assert torch.cuda.is_available(), 'CUDA is not available.'
+  torch.backends.cudnn.enabled   = True
+  torch.backends.cudnn.benchmark = False
+  torch.backends.cudnn.deterministic = True
+  torch.set_num_threads( xargs.workers )
+  prepare_seed(xargs.rand_seed)
+  logger = prepare_logger(args)
+
+  train_data, valid_data, xshape, class_num = get_datasets(xargs.dataset, xargs.data_path, -1)
+  if xargs.dataset == 'cifar10' or xargs.dataset == 'cifar100':
+    split_Fpath = 'configs/nas-benchmark/cifar-split.txt'
+    cifar_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = cifar_split.train, cifar_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  elif xargs.dataset.startswith('ImageNet16'):
+    split_Fpath = 'configs/nas-benchmark/{:}-split.txt'.format(xargs.dataset)
+    imagenet16_split = load_config(split_Fpath, None, None)
+    train_split, valid_split = imagenet16_split.train, imagenet16_split.valid
+    logger.log('Load split file from {:}'.format(split_Fpath))
+  else:
+    raise ValueError('invalid dataset : {:}'.format(xargs.dataset))
+  config_path = 'configs/nas-benchmark/algos/SETN.config'
+  config = load_config(config_path, {'class_num': class_num, 'xshape': xshape}, logger)
+  # To split data
+  train_data_v2 = deepcopy(train_data)
+  train_data_v2.transform = valid_data.transform
+  valid_data    = train_data_v2
+  search_data   = SearchDataset(xargs.dataset, train_data, train_split, valid_split)
+  # data loader
+  search_loader = torch.utils.data.DataLoader(search_data, batch_size=config.batch_size, shuffle=True , num_workers=xargs.workers, pin_memory=True)
+  valid_loader  = torch.utils.data.DataLoader(valid_data, batch_size=config.batch_size, sampler=torch.utils.data.sampler.SubsetRandomSampler(valid_split), num_workers=xargs.workers, pin_memory=True)
+  logger.log('||||||| {:10s} ||||||| Search-Loader-Num={:}, Valid-Loader-Num={:}, batch size={:}'.format(xargs.dataset, len(search_loader), len(valid_loader), config.batch_size))
+  logger.log('||||||| {:10s} ||||||| Config={:}'.format(xargs.dataset, config))
+
+  search_space = get_search_spaces('cell', xargs.search_space_name)
+  model_config = dict2config({'name': 'SETN', 'C': xargs.channel, 'N': xargs.num_cells,
+                              'max_nodes': xargs.max_nodes, 'num_classes': class_num,
+                              'space'    : search_space}, None)
+  search_model = get_cell_based_tiny_net(model_config)
+  
+  w_optimizer, w_scheduler, criterion = get_optim_scheduler(search_model.get_weights(), config)
+  a_optimizer = torch.optim.Adam(search_model.get_alphas(), lr=xargs.arch_learning_rate, betas=(0.5, 0.999), weight_decay=xargs.arch_weight_decay)
+  logger.log('w-optimizer : {:}'.format(w_optimizer))
+  logger.log('a-optimizer : {:}'.format(a_optimizer))
+  logger.log('w-scheduler : {:}'.format(w_scheduler))
+  logger.log('criterion   : {:}'.format(criterion))
+  flop, param  = get_model_infos(search_model, xshape)
+  #logger.log('{:}'.format(search_model))
+  logger.log('FLOP = {:.2f} M, Params = {:.2f} MB'.format(flop, param))
+
+  last_info, model_base_path, model_best_path = logger.path('info'), logger.path('model'), logger.path('best')
+  network, criterion = torch.nn.DataParallel(search_model).cuda(), criterion.cuda()
+
+  if last_info.exists(): # automatically resume from previous checkpoint
+    logger.log("=> loading checkpoint of the last-info '{:}' start".format(last_info))
+    last_info   = torch.load(last_info)
+    start_epoch = last_info['epoch']
+    checkpoint  = torch.load(last_info['last_checkpoint'])
+    genotypes   = checkpoint['genotypes']
+    valid_accuracies = checkpoint['valid_accuracies']
+    search_model.load_state_dict( checkpoint['search_model'] )
+    w_scheduler.load_state_dict ( checkpoint['w_scheduler'] )
+    w_optimizer.load_state_dict ( checkpoint['w_optimizer'] )
+    a_optimizer.load_state_dict ( checkpoint['a_optimizer'] )
+    logger.log("=> loading checkpoint of the last-info '{:}' start with {:}-th epoch.".format(last_info, start_epoch))
+  else:
+    logger.log("=> do not find the last-info file : {:}".format(last_info))
+    start_epoch, valid_accuracies, genotypes = 0, {'best': -1}, {}
+
+  # start training
+  start_time, epoch_time, total_epoch = time.time(), AverageMeter(), config.epochs + config.warmup
+  for epoch in range(start_epoch, total_epoch):
+    w_scheduler.update(epoch, 0.0)
+    need_time = 'Time Left: {:}'.format( convert_secs2time(epoch_time.val * (total_epoch-epoch), True) )
+    epoch_str = '{:03d}-{:03d}'.format(epoch, total_epoch)
+    logger.log('\n[Search the {:}-th epoch] {:}, LR={:}'.format(epoch_str, need_time, min(w_scheduler.get_lr())))
+
+    search_w_loss, search_w_top1, search_w_top5 = search_func(search_loader, network, criterion, w_scheduler, w_optimizer, a_optimizer, epoch_str, xargs.print_freq, logger)
+    logger.log('[{:}] searching : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, search_w_loss, search_w_top1, search_w_top5))
+    search_model.set_cal_mode('urs')
+    valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('[{:}] URS---evaluate : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss, valid_a_top1, valid_a_top5))
+    search_model.set_cal_mode('joint')
+    valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('[{:}] JOINT-evaluate : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss, valid_a_top1, valid_a_top5))
+    search_model.set_cal_mode('select')
+    valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('[{:}] Selec-evaluate : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%'.format(epoch_str, valid_a_loss, valid_a_top1, valid_a_top5))
+    # check the best accuracy
+    valid_accuracies[epoch] = valid_a_top1
+    if valid_a_top1 > valid_accuracies['best']:
+      valid_accuracies['best'] = valid_a_top1
+      genotypes['best']        = search_model.genotype()
+      find_best = True
+    else: find_best = False
+
+    genotypes[epoch] = search_model.genotype()
+    logger.log('<<<--->>> The {:}-th epoch : {:}'.format(epoch_str, genotypes[epoch]))
+    # save checkpoint
+    save_path = save_checkpoint({'epoch' : epoch + 1,
+                'args'  : deepcopy(xargs),
+                'search_model': search_model.state_dict(),
+                'w_optimizer' : w_optimizer.state_dict(),
+                'a_optimizer' : a_optimizer.state_dict(),
+                'w_scheduler' : w_scheduler.state_dict(),
+                'genotypes'   : genotypes,
+                'valid_accuracies' : valid_accuracies},
+                model_base_path, logger)
+    last_info = save_checkpoint({
+          'epoch': epoch + 1,
+          'args' : deepcopy(args),
+          'last_checkpoint': save_path,
+          }, logger.path('info'), logger)
+    if find_best:
+      logger.log('<<<--->>> The {:}-th epoch : find the highest validation accuracy : {:.2f}%.'.format(epoch_str, valid_a_top1))
+      copy_checkpoint(model_base_path, model_best_path, logger)
+    with torch.no_grad():
+      logger.log('arch-parameters :\n{:}'.format( nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu() ))
+    # measure elapsed time
+    epoch_time.update(time.time() - start_time)
+    start_time = time.time()
+
+  # sampling
+  with torch.no_grad():
+    logger.log('arch-parameters :\n{:}'.format( nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu() ))
+  selected_archs = set()
+  while len(selected_archs) < xargs.select_num:
+    architecture = search_model.dync_genotype()
+    selected_archs.add( architecture )
+  logger.log('select {:} architectures based on the learned arch-parameters'.format( len(selected_archs) ))
+
+  best_arch, best_acc = None, -1
+  state_dict = deepcopy( network.state_dict() )
+  for index, arch in enumerate(selected_archs):
+    with torch.no_grad():
+      search_model.set_cal_mode('dynamic', arch)
+      network.load_state_dict( deepcopy(state_dict) )
+      valid_a_loss , valid_a_top1 , valid_a_top5  = valid_func(valid_loader, network, criterion)
+    logger.log('{:} [{:03d}/{:03d}] : {:125s}, loss={:.3f}, accuracy={:.3f}%'.format(time_string(), index, len(selected_archs), str(arch), valid_a_loss , valid_a_top1))
+    if best_arch is None or best_acc < valid_a_top1:
+      best_arch, best_acc = arch, valid_a_top1
+  logger.log('Find the best one : {:} with accuracy={:.2f}%'.format(best_arch, best_acc))
+
+  logger.log('\n' + '-'*100)
+  # check the performance from the architecture dataset
+  """
+  if xargs.arch_nas_dataset is None or not os.path.isfile(xargs.arch_nas_dataset):
+    logger.log('Can not find the architecture dataset : {:}.'.format(xargs.arch_nas_dataset))
+  else:
+    nas_bench = TinyNASBenchmarkAPI(xargs.arch_nas_dataset)
+    geno      = best_arch
+    logger.log('The last model is {:}'.format(geno))
+    info = nas_bench.query_by_arch( geno )
+    if info is None: logger.log('Did not find this architecture : {:}.'.format(geno))
+    else           : logger.log('{:}'.format(info))
+    logger.log('-'*100)
+  """
+  logger.close()
+  
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser("SETN")
+  parser.add_argument('--data_path',          type=str,   help='Path to dataset')
+  parser.add_argument('--dataset',            type=str,   choices=['cifar10', 'cifar100', 'ImageNet16-120'], help='Choose between Cifar10/100 and ImageNet-16.')
+  # channels and number-of-cells
+  parser.add_argument('--search_space_name',  type=str,   help='The search space name.')
+  parser.add_argument('--max_nodes',          type=int,   help='The maximum number of nodes.')
+  parser.add_argument('--channel',            type=int,   help='The number of channels.')
+  parser.add_argument('--num_cells',          type=int,   help='The number of cells in one stage.')
+  parser.add_argument('--select_num',         type=int,   help='The number of selected architectures to evaluate.')
+  # architecture leraning rate
+  parser.add_argument('--arch_learning_rate', type=float, default=3e-4, help='learning rate for arch encoding')
+  parser.add_argument('--arch_weight_decay',  type=float, default=1e-3, help='weight decay for arch encoding')
+  # log
+  parser.add_argument('--workers',            type=int,   default=2,    help='number of data loading workers (default: 2)')
+  parser.add_argument('--save_dir',           type=str,   help='Folder to save checkpoints and log.')
+  parser.add_argument('--arch_nas_dataset',   type=str,   help='The path to load the architecture dataset (tiny-nas-benchmark).')
+  parser.add_argument('--print_freq',         type=int,   help='print frequency (default: 200)')
+  parser.add_argument('--rand_seed',          type=int,   help='manual seed')
+  args = parser.parse_args()
+  if args.rand_seed is None or args.rand_seed < 0: args.rand_seed = random.randint(1, 100000)
+  main(args)

lib/datasets/SearchDatasetWrap.py

@@ -12,7 +12,7 @@ class SearchDataset(data.Dataset):
     self.length      = len(self.train_split)
 
   def __repr__(self):
-    return ('{name}(name={datasetname}, length={length})'.format(name=self.__class__.__name__, **self.__dict__))
+    return ('{name}(name={datasetname}, train={tr_L}, valid={val_L})'.format(name=self.__class__.__name__, tr_L=len(self.train_split), val_L=len(self.valid_split)))
 
   def __len__(self):
     return self.length

lib/models/__init__.py

@@ -3,11 +3,36 @@
 ##################################################
 import torch
 from os import path as osp
-# our modules
+# useful modules
 from config_utils import dict2config
 from .SharedUtils import change_key
 from .clone_weights import init_from_model
 
+# Cell-based NAS Models
+def get_cell_based_tiny_net(config):
+  if config.name == 'DARTS-V1':
+    from .cell_searchs import TinyNetworkDartsV1
+    return TinyNetworkDartsV1(config.C, config.N, config.max_nodes, config.num_classes, config.space)
+  elif config.name == 'DARTS-V2':
+    from .cell_searchs import TinyNetworkDartsV2
+    return TinyNetworkDartsV2(config.C, config.N, config.max_nodes, config.num_classes, config.space)
+  elif config.name == 'GDAS':
+    from .cell_searchs import TinyNetworkGDAS
+    return TinyNetworkGDAS(config.C, config.N, config.max_nodes, config.num_classes, config.space)
+  elif config.name == 'SETN':
+    from .cell_searchs import TinyNetworkSETN
+    return TinyNetworkSETN(config.C, config.N, config.max_nodes, config.num_classes, config.space)
+  else:
+    raise ValueError('invalid network name : {:}'.format(config.name))
+
+# obtain the search space, i.e., a dict mapping the operation name into a python-function for this op
+def get_search_spaces(xtype, name):
+  if xtype == 'cell':
+    from .cell_operations import SearchSpaceNames
+    return SearchSpaceNames[name]
+  else:
+    raise ValueError('invalid search-space type is {:}'.format(xtype))
+
 
 def get_cifar_models(config):
   from .CifarResNet      import CifarResNet
@@ -22,9 +47,9 @@ def get_cifar_models(config):
     else:
       raise ValueError('invalid module type : {:}'.format(config.arch))
   elif super_type.startswith('infer'):
-    from .infers import InferWidthCifarResNet
-    from .infers import InferDepthCifarResNet
-    from .infers import InferCifarResNet
+    from .shape_infers import InferWidthCifarResNet
+    from .shape_infers import InferDepthCifarResNet
+    from .shape_infers import InferCifarResNet
     assert len(super_type.split('-')) == 2, 'invalid super_type : {:}'.format(super_type)
     infer_mode = super_type.split('-')[1]
     if infer_mode == 'width':
@@ -46,8 +71,8 @@ def get_imagenet_models(config):
     assert len(super_type.split('-')) == 2, 'invalid super_type : {:}'.format(super_type)
     infer_mode = super_type.split('-')[1]
     if infer_mode == 'shape':
-      from .infers import InferImagenetResNet
-      from .infers import InferMobileNetV2
+      from .shape_infers import InferImagenetResNet
+      from .shape_infers import InferMobileNetV2
       if config.arch == 'resnet':
         return InferImagenetResNet(config.block_name, config.layers, config.xblocks, config.xchannels, config.deep_stem, config.class_num, config.zero_init_residual)
       elif config.arch == "MobileNetV2":
@@ -72,9 +97,9 @@ def obtain_model(config):
 def obtain_search_model(config):
   if config.dataset == 'cifar':
     if config.arch == 'resnet':
-      from .searchs import SearchWidthCifarResNet
-      from .searchs import SearchDepthCifarResNet
-      from .searchs import SearchShapeCifarResNet
+      from .shape_searchs import SearchWidthCifarResNet
+      from .shape_searchs import SearchDepthCifarResNet
+      from .shape_searchs import SearchShapeCifarResNet
       if config.search_mode == 'width':
         return SearchWidthCifarResNet(config.module, config.depth, config.class_num)
       elif config.search_mode == 'depth':
@@ -85,7 +110,7 @@ def obtain_search_model(config):
     else:
       raise ValueError('invalid arch : {:} for dataset [{:}]'.format(config.arch, config.dataset))
   elif config.dataset == 'imagenet':
-    from .searchs import SearchShapeImagenetResNet
+    from .shape_searchs import SearchShapeImagenetResNet
     assert config.search_mode == 'shape', 'invalid search-mode : {:}'.format( config.search_mode )
     if config.arch == 'resnet':
       return SearchShapeImagenetResNet(config.block_name, config.layers, config.deep_stem, config.class_num)

lib/models/cell_operations.py

@@ -1,7 +1,7 @@
 import torch
 import torch.nn as nn
 
-__all__ = ['OPS', 'ReLUConvBN', 'SearchSpaceNames']
+__all__ = ['OPS', 'ReLUConvBN', 'ResNetBasicblock', 'SearchSpaceNames']
 
 OPS = {
   'none'         : lambda C_in, C_out, stride: Zero(C_in, C_out, stride),
@@ -14,8 +14,60 @@ OPS = {
 }
 
 CONNECT_NAS_BENCHMARK  = ['none', 'skip_connect', 'nor_conv_3x3']
+AA_NAS_BENCHMARK       = ['none', 'skip_connect', 'nor_conv_1x1', 'nor_conv_3x3', 'avg_pool_3x3']
 
-SearchSpaceNames = {'connect-nas' : CONNECT_NAS_BENCHMARK}
+SearchSpaceNames = {'connect-nas' : CONNECT_NAS_BENCHMARK,
+                    'aa-nas'      : AA_NAS_BENCHMARK}
+
+
+class ReLUConvBN(nn.Module):
+
+  def __init__(self, C_in, C_out, kernel_size, stride, padding, dilation):
+    super(ReLUConvBN, self).__init__()
+    self.op = nn.Sequential(
+      nn.ReLU(inplace=False),
+      nn.Conv2d(C_in, C_out, kernel_size, stride=stride, padding=padding, dilation=dilation, bias=False),
+      nn.BatchNorm2d(C_out)
+    )
+
+  def forward(self, x):
+    return self.op(x)
+
+
+class ResNetBasicblock(nn.Module):
+
+  def __init__(self, inplanes, planes, stride):
+    super(ResNetBasicblock, self).__init__()
+    assert stride == 1 or stride == 2, 'invalid stride {:}'.format(stride)
+    self.conv_a = ReLUConvBN(inplanes, planes, 3, stride, 1, 1)
+    self.conv_b = ReLUConvBN(  planes, planes, 3,      1, 1, 1)
+    if stride == 2:
+      self.downsample = nn.Sequential(
+                           nn.AvgPool2d(kernel_size=2, stride=2, padding=0),
+                           nn.Conv2d(inplanes, planes, kernel_size=1, stride=1, padding=0, bias=False))
+    elif inplanes != planes:
+      self.downsample = ReLUConvBN(inplanes, planes, 1, 1, 0, 1)
+    else:
+      self.downsample = None
+    self.in_dim  = inplanes
+    self.out_dim = planes
+    self.stride  = stride
+    self.num_conv = 2
+
+  def extra_repr(self):
+    string = '{name}(inC={in_dim}, outC={out_dim}, stride={stride})'.format(name=self.__class__.__name__, **self.__dict__)
+    return string
+
+  def forward(self, inputs):
+
+    basicblock = self.conv_a(inputs)
+    basicblock = self.conv_b(basicblock)
+
+    if self.downsample is not None:
+      residual = self.downsample(inputs)
+    else:
+      residual = inputs
+    return residual + basicblock
 
 
 class POOLING(nn.Module):
@@ -36,20 +88,6 @@ class POOLING(nn.Module):
     return self.op(x)
 
 
-class ReLUConvBN(nn.Module):
-
-  def __init__(self, C_in, C_out, kernel_size, stride, padding, dilation):
-    super(ReLUConvBN, self).__init__()
-    self.op = nn.Sequential(
-      nn.ReLU(inplace=False),
-      nn.Conv2d(C_in, C_out, kernel_size, stride=stride, padding=padding, dilation=dilation, bias=False),
-      nn.BatchNorm2d(C_out)
-    )
-
-  def forward(self, x):
-    return self.op(x)
-
-
 class Identity(nn.Module):
 
   def __init__(self):

lib/models/cell_searchs/__init__.py

@@ -0,0 +1,4 @@
+from .search_model_darts_v1 import TinyNetworkDartsV1
+from .search_model_darts_v2 import TinyNetworkDartsV2
+from .search_model_gdas     import TinyNetworkGDAS
+from .search_model_setn     import TinyNetworkSETN

lib/models/cell_searchs/cells.py

@@ -2,7 +2,7 @@ import math, torch
 import torch.nn as nn
 import torch.nn.functional as F
 from copy import deepcopy
-from .operations import OPS, ReLUConvBN
+from ..cell_operations import OPS
 
 
 class SearchCell(nn.Module):
@@ -113,84 +113,3 @@ class SearchCell(nn.Module):
         inter_nodes.append( self.edges[node_str][op_index]( nodes[j] ) )
       nodes.append( sum(inter_nodes) )
     return nodes[-1]
-
-
-class InferCell(nn.Module):
-
-  def __init__(self, genotype, C_in, C_out, stride):
-    super(InferCell, self).__init__()
-
-    self.layers  = nn.ModuleList()
-    self.node_IN = []
-    self.node_IX = []
-    self.genotype = deepcopy(genotype)
-    for i in range(1, len(genotype)):
-      node_info = genotype[i-1]
-      cur_index = []
-      cur_innod = []
-      for (op_name, op_in) in node_info:
-        if op_in == 0:
-          layer = OPS[op_name](C_in , C_out, stride)
-        else:
-          layer = OPS[op_name](C_out, C_out,      1)
-        cur_index.append( len(self.layers) )
-        cur_innod.append( op_in )
-        self.layers.append( layer )
-      self.node_IX.append( cur_index )
-      self.node_IN.append( cur_innod )
-    self.nodes   = len(genotype)
-    self.in_dim  = C_in
-    self.out_dim = C_out
-
-  def extra_repr(self):
-    string = 'info :: nodes={nodes}, inC={in_dim}, outC={out_dim}'.format(**self.__dict__)
-    laystr = []
-    for i, (node_layers, node_innods) in enumerate(zip(self.node_IX,self.node_IN)):
-      y = ['I{:}-L{:}'.format(_ii, _il) for _il, _ii in zip(node_layers, node_innods)]
-      x = '{:}<-({:})'.format(i+1, ','.join(y))
-      laystr.append( x )
-    return string + ', [{:}]'.format( ' | '.join(laystr) ) + ', {:}'.format(self.genotype.tostr())
-
-  def forward(self, inputs):
-    nodes = [inputs]
-    for i, (node_layers, node_innods) in enumerate(zip(self.node_IX,self.node_IN)):
-      node_feature = sum( self.layers[_il](nodes[_ii]) for _il, _ii in zip(node_layers, node_innods) )
-      nodes.append( node_feature )
-    return nodes[-1]
-
-
-
-class ResNetBasicblock(nn.Module):
-
-  def __init__(self, inplanes, planes, stride):
-    super(ResNetBasicblock, self).__init__()
-    assert stride == 1 or stride == 2, 'invalid stride {:}'.format(stride)
-    self.conv_a = ReLUConvBN(inplanes, planes, 3, stride, 1, 1)
-    self.conv_b = ReLUConvBN(  planes, planes, 3,      1, 1, 1)
-    if stride == 2:
-      self.downsample = nn.Sequential(
-                           nn.AvgPool2d(kernel_size=2, stride=2, padding=0),
-                           nn.Conv2d(inplanes, planes, kernel_size=1, stride=1, padding=0, bias=False))
-    elif inplanes != planes:
-      self.downsample = ReLUConvBN(inplanes, planes, 1, 1, 0, 1)
-    else:
-      self.downsample = None
-    self.in_dim  = inplanes
-    self.out_dim = planes
-    self.stride  = stride
-    self.num_conv = 2
-
-  def extra_repr(self):
-    string = '{name}(inC={in_dim}, outC={out_dim}, stride={stride})'.format(name=self.__class__.__name__, **self.__dict__)
-    return string
-
-  def forward(self, inputs):
-
-    basicblock = self.conv_a(inputs)
-    basicblock = self.conv_b(basicblock)
-
-    if self.downsample is not None:
-      residual = self.downsample(inputs)
-    else:
-      residual = inputs
-    return residual + basicblock

lib/models/cell_searchs/genotypes.py

@@ -0,0 +1,158 @@
+from copy import deepcopy
+
+
+
+def get_combination(space, num):
+  combs = []
+  for i in range(num):
+    if i == 0:
+      for func in space:
+        combs.append( [(func, i)] )
+    else:
+      new_combs = []
+      for string in combs:
+        for func in space:
+          xstring = string + [(func, i)]
+          new_combs.append( xstring )
+      combs = new_combs
+  return combs
+  
+
+
+class Structure:
+
+  def __init__(self, genotype):
+    assert isinstance(genotype, list) or isinstance(genotype, tuple), 'invalid class of genotype : {:}'.format(type(genotype))
+    self.node_num = len(genotype) + 1
+    self.nodes    = []
+    self.node_N   = []
+    for idx, node_info in enumerate(genotype):
+      assert isinstance(node_info, list) or isinstance(node_info, tuple), 'invalid class of node_info : {:}'.format(type(node_info))
+      assert len(node_info) >= 1, 'invalid length : {:}'.format(len(node_info))
+      for node_in in node_info:
+        assert isinstance(node_in, list) or isinstance(node_in, tuple), 'invalid class of in-node : {:}'.format(type(node_in))
+        assert len(node_in) == 2 and node_in[1] <= idx, 'invalid in-node : {:}'.format(node_in)
+      self.node_N.append( len(node_info) )
+      self.nodes.append( tuple(deepcopy(node_info)) )
+
+  def tolist(self, remove_str):
+    # convert this class to the list, if remove_str is 'none', then remove the 'none' operation.
+    # note that we re-order the input node in this function
+    # return the-genotype-list and success [if unsuccess, it is not a connectivity]
+    genotypes = []
+    for node_info in self.nodes:
+      node_info = list( node_info )
+      node_info = sorted(node_info, key=lambda x: (x[1], x[0]))
+      node_info = tuple(filter(lambda x: x[0] != remove_str, node_info))
+      if len(node_info) == 0: return None, False
+      genotypes.append( node_info )
+    return genotypes, True
+
+  def node(self, index):
+    assert index > 0 and index <= len(self), 'invalid index={:} < {:}'.format(index, len(self))
+    return self.nodes[index]
+
+  def tostr(self):
+    strings = []
+    for node_info in self.nodes:
+      string = '|'.join([x[0]+'~{:}'.format(x[1]) for x in node_info])
+      string = '|{:}|'.format(string)
+      strings.append( string )
+    return '+'.join(strings)
+
+  def __repr__(self):
+    return ('{name}({node_num} nodes with {node_info})'.format(name=self.__class__.__name__, node_info=self.tostr(), **self.__dict__))
+
+  def __len__(self):
+    return len(self.nodes) + 1
+
+  def __getitem__(self, index):
+    return self.nodes[index]
+
+  @staticmethod
+  def str2structure(xstr):
+    assert isinstance(xstr, str), 'must take string (not {:}) as input'.format(type(xstr))
+    nodestrs = xstr.split('+')
+    genotypes = []
+    for i, node_str in enumerate(nodestrs):
+      inputs = list(filter(lambda x: x != '', node_str.split('|')))
+      for xinput in inputs: assert len(xinput.split('~')) == 2, 'invalid input length : {:}'.format(xinput)
+      inputs = ( xi.split('~') for xi in inputs )
+      input_infos = tuple( (op, int(IDX)) for (op, IDX) in inputs)
+      genotypes.append( input_infos )
+    return Structure( genotypes )
+
+  @staticmethod
+  def str2fullstructure(xstr, default_name='none'):
+    assert isinstance(xstr, str), 'must take string (not {:}) as input'.format(type(xstr))
+    nodestrs = xstr.split('+')
+    genotypes = []
+    for i, node_str in enumerate(nodestrs):
+      inputs = list(filter(lambda x: x != '', node_str.split('|')))
+      for xinput in inputs: assert len(xinput.split('~')) == 2, 'invalid input length : {:}'.format(xinput)
+      inputs = ( xi.split('~') for xi in inputs )
+      input_infos = list( (op, int(IDX)) for (op, IDX) in inputs)
+      all_in_nodes= list(x[1] for x in input_infos)
+      for j in range(i):
+        if j not in all_in_nodes: input_infos.append((default_name, j))
+      node_info = sorted(input_infos, key=lambda x: (x[1], x[0]))
+      genotypes.append( tuple(node_info) )
+    return Structure( genotypes )
+
+  @staticmethod
+  def gen_all(search_space, num, return_ori):
+    assert isinstance(search_space, list) or isinstance(search_space, tuple), 'invalid class of search-space : {:}'.format(type(search_space))
+    assert num >= 2, 'There should be at least two nodes in a neural cell instead of {:}'.format(num)
+    all_archs = get_combination(search_space, 1)
+    for i, arch in enumerate(all_archs):
+      all_archs[i] = [ tuple(arch) ]
+  
+    for inode in range(2, num):
+      cur_nodes = get_combination(search_space, inode)
+      new_all_archs = []
+      for previous_arch in all_archs:
+        for cur_node in cur_nodes:
+          new_all_archs.append( previous_arch + [tuple(cur_node)] )
+      all_archs = new_all_archs
+    if return_ori:
+      return all_archs
+    else:
+      return [Structure(x) for x in all_archs]
+
+
+
+ResNet_CODE = Structure(
+  [(('nor_conv_3x3', 0), ), # node-1 
+   (('nor_conv_3x3', 1), ), # node-2
+   (('skip_connect', 0), ('skip_connect', 2))] # node-3
+  )
+
+AllConv3x3_CODE = Structure(
+  [(('nor_conv_3x3', 0), ), # node-1 
+   (('nor_conv_3x3', 0), ('nor_conv_3x3', 1)), # node-2
+   (('nor_conv_3x3', 0), ('nor_conv_3x3', 1), ('nor_conv_3x3', 2))] # node-3
+  )
+
+AllFull_CODE = Structure(
+  [(('skip_connect', 0), ('nor_conv_1x1', 0), ('nor_conv_3x3', 0), ('avg_pool_3x3', 0)), # node-1 
+   (('skip_connect', 0), ('nor_conv_1x1', 0), ('nor_conv_3x3', 0), ('avg_pool_3x3', 0), ('skip_connect', 1), ('nor_conv_1x1', 1), ('nor_conv_3x3', 1), ('avg_pool_3x3', 1)), # node-2
+   (('skip_connect', 0), ('nor_conv_1x1', 0), ('nor_conv_3x3', 0), ('avg_pool_3x3', 0), ('skip_connect', 1), ('nor_conv_1x1', 1), ('nor_conv_3x3', 1), ('avg_pool_3x3', 1), ('skip_connect', 2), ('nor_conv_1x1', 2), ('nor_conv_3x3', 2), ('avg_pool_3x3', 2))] # node-3
+  )
+
+AllConv1x1_CODE = Structure(
+  [(('nor_conv_1x1', 0), ), # node-1 
+   (('nor_conv_1x1', 0), ('nor_conv_1x1', 1)), # node-2
+   (('nor_conv_1x1', 0), ('nor_conv_1x1', 1), ('nor_conv_1x1', 2))] # node-3
+  )
+
+AllIdentity_CODE = Structure(
+  [(('skip_connect', 0), ), # node-1 
+   (('skip_connect', 0), ('skip_connect', 1)), # node-2
+   (('skip_connect', 0), ('skip_connect', 1), ('skip_connect', 2))] # node-3
+  )
+
+architectures = {'resnet'  : ResNet_CODE,
+                 'all_c3x3': AllConv3x3_CODE,
+                 'all_c1x1': AllConv1x1_CODE,
+                 'all_idnt': AllIdentity_CODE,
+                 'all_full': AllFull_CODE}

lib/models/cell_searchs/search_cells.py

@@ -0,0 +1,134 @@
+import math, random, torch
+import warnings
+import torch.nn as nn
+import torch.nn.functional as F
+from copy import deepcopy
+from ..cell_operations import OPS
+
+
+class SearchCell(nn.Module):
+
+  def __init__(self, C_in, C_out, stride, max_nodes, op_names):
+    super(SearchCell, self).__init__()
+
+    self.op_names  = deepcopy(op_names)
+    self.edges     = nn.ModuleDict()
+    self.max_nodes = max_nodes
+    self.in_dim    = C_in
+    self.out_dim   = C_out
+    for i in range(1, max_nodes):
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        if j == 0:
+          xlists = [OPS[op_name](C_in , C_out, stride) for op_name in op_names]
+        else:
+          xlists = [OPS[op_name](C_in , C_out,      1) for op_name in op_names]
+        self.edges[ node_str ] = nn.ModuleList( xlists )
+    self.edge_keys  = sorted(list(self.edges.keys()))
+    self.edge2index = {key:i for i, key in enumerate(self.edge_keys)}
+    self.num_edges  = len(self.edges)
+
+  def extra_repr(self):
+    string = 'info :: {max_nodes} nodes, inC={in_dim}, outC={out_dim}'.format(**self.__dict__)
+    return string
+
+  def forward(self, inputs, weightss):
+    nodes = [inputs]
+    for i in range(1, self.max_nodes):
+      inter_nodes = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        weights  = weightss[ self.edge2index[node_str] ]
+        inter_nodes.append( sum( layer(nodes[j]) * w for layer, w in zip(self.edges[node_str], weights) ) )
+      nodes.append( sum(inter_nodes) )
+    return nodes[-1]
+
+  # GDAS
+  def forward_gdas(self, inputs, alphas, _tau):
+    avoid_zero = 0
+    while True:
+      gumbels = -torch.empty_like(alphas).exponential_().log()
+      logits  = (alphas.log_softmax(dim=1) + gumbels) / _tau
+      probs   = nn.functional.softmax(logits, dim=1)
+      index   = probs.max(-1, keepdim=True)[1]
+      one_h   = torch.zeros_like(logits).scatter_(-1, index, 1.0)
+      hardwts = one_h - probs.detach() + probs
+      if (torch.isinf(gumbels).any()) or (torch.isinf(probs).any()) or (torch.isnan(probs).any()):
+        continue # avoid the numerical error
+      nodes   = [inputs]
+      for i in range(1, self.max_nodes):
+        inter_nodes = []
+        for j in range(i):
+          node_str = '{:}<-{:}'.format(i, j)
+          weights  = hardwts[ self.edge2index[node_str] ]
+          argmaxs  = index[ self.edge2index[node_str] ].item()
+          weigsum  = sum( weights[_ie] * edge(nodes[j]) if _ie == argmaxs else weights[_ie] for _ie, edge in enumerate(self.edges[node_str]) )
+          inter_nodes.append( weigsum )
+        nodes.append( sum(inter_nodes) )
+      avoid_zero += 1
+      if nodes[-1].sum().item() == 0:
+        if avoid_zero < 10: continue
+        else:
+          warnings.warn('get zero outputs with avoid_zero={:}'.format(avoid_zero))
+          break
+      else:
+        break
+    return nodes[-1]
+
+  # joint
+  def forward_joint(self, inputs, weightss):
+    nodes = [inputs]
+    for i in range(1, self.max_nodes):
+      inter_nodes = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        weights  = weightss[ self.edge2index[node_str] ]
+        aggregation = sum( layer(nodes[j]) * w for layer, w in zip(self.edges[node_str], weights) ) / weights.numel()
+        inter_nodes.append( aggregation )
+      nodes.append( sum(inter_nodes) )
+    return nodes[-1]
+
+  # uniform random sampling per iteration
+  def forward_urs(self, inputs):
+    nodes = [inputs]
+    for i in range(1, self.max_nodes):
+      while True: # to avoid select zero for all ops
+        sops, has_non_zero = [], False
+        for j in range(i):
+          node_str   = '{:}<-{:}'.format(i, j)
+          candidates = self.edges[node_str]
+          select_op  = random.choice(candidates)
+          sops.append( select_op )
+          if not hasattr(select_op, 'is_zero') or select_op.is_zero == False: has_non_zero=True
+        if has_non_zero: break
+      inter_nodes = []
+      for j, select_op in enumerate(sops):
+        inter_nodes.append( select_op(nodes[j]) )
+      nodes.append( sum(inter_nodes) )
+    return nodes[-1]
+
+  # select the argmax
+  def forward_select(self, inputs, weightss):
+    nodes = [inputs]
+    for i in range(1, self.max_nodes):
+      inter_nodes = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        weights  = weightss[ self.edge2index[node_str] ]
+        inter_nodes.append( self.edges[node_str][ weights.argmax().item() ]( nodes[j] ) )
+        #inter_nodes.append( sum( layer(nodes[j]) * w for layer, w in zip(self.edges[node_str], weights) ) )
+      nodes.append( sum(inter_nodes) )
+    return nodes[-1]
+
+  # forward with a specific structure
+  def forward_dynamic(self, inputs, structure):
+    nodes = [inputs]
+    for i in range(1, self.max_nodes):
+      cur_op_node = structure.nodes[i-1]
+      inter_nodes = []
+      for op_name, j in cur_op_node:
+        node_str = '{:}<-{:}'.format(i, j)
+        op_index = self.op_names.index( op_name )
+        inter_nodes.append( self.edges[node_str][op_index]( nodes[j] ) )
+      nodes.append( sum(inter_nodes) )
+    return nodes[-1]

lib/models/cell_searchs/search_model_darts_v1.py

@@ -0,0 +1,93 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+########################################################
+# DARTS: Differentiable Architecture Search, ICLR 2019 #
+########################################################
+import torch
+import torch.nn as nn
+from copy import deepcopy
+from ..cell_operations import ResNetBasicblock
+from .search_cells     import SearchCell
+from .genotypes        import Structure
+
+
+class TinyNetworkDartsV1(nn.Module):
+
+  def __init__(self, C, N, max_nodes, num_classes, search_space):
+    super(TinyNetworkDartsV1, self).__init__()
+    self._C        = C
+    self._layerN   = N
+    self.max_nodes = max_nodes
+    self.stem = nn.Sequential(
+                    nn.Conv2d(3, C, kernel_size=3, padding=1, bias=False),
+                    nn.BatchNorm2d(C))
+  
+    layer_channels   = [C    ] * N + [C*2 ] + [C*2  ] * N + [C*4 ] + [C*4  ] * N    
+    layer_reductions = [False] * N + [True] + [False] * N + [True] + [False] * N
+
+    C_prev, num_edge, edge2index = C, None, None
+    self.cells = nn.ModuleList()
+    for index, (C_curr, reduction) in enumerate(zip(layer_channels, layer_reductions)):
+      if reduction:
+        cell = ResNetBasicblock(C_prev, C_curr, 2)
+      else:
+        cell = SearchCell(C_prev, C_curr, 1, max_nodes, search_space)
+        if num_edge is None: num_edge, edge2index = cell.num_edges, cell.edge2index
+        else: assert num_edge == cell.num_edges and edge2index == cell.edge2index, 'invalid {:} vs. {:}.'.format(num_edge, cell.num_edges)
+      self.cells.append( cell )
+      C_prev = cell.out_dim
+    self.op_names   = deepcopy( search_space )
+    self._Layer     = len(self.cells)
+    self.edge2index = edge2index
+    self.lastact    = nn.Sequential(nn.BatchNorm2d(C_prev), nn.ReLU(inplace=True))
+    self.global_pooling = nn.AdaptiveAvgPool2d(1)
+    self.classifier = nn.Linear(C_prev, num_classes)
+    self.arch_parameters = nn.Parameter( 1e-3*torch.randn(num_edge, len(search_space)) )
+
+  def get_weights(self):
+    xlist = list( self.stem.parameters() ) + list( self.cells.parameters() )
+    xlist+= list( self.lastact.parameters() ) + list( self.global_pooling.parameters() )
+    xlist+= list( self.classifier.parameters() )
+    return xlist
+
+  def get_alphas(self):
+    return [self.arch_parameters]
+
+  def get_message(self):
+    string = self.extra_repr()
+    for i, cell in enumerate(self.cells):
+      string += '\n {:02d}/{:02d} :: {:}'.format(i, len(self.cells), cell.extra_repr())
+    return string
+
+  def extra_repr(self):
+    return ('{name}(C={_C}, Max-Nodes={max_nodes}, N={_layerN}, L={_Layer})'.format(name=self.__class__.__name__, **self.__dict__))
+
+  def genotype(self):
+    genotypes = []
+    for i in range(1, self.max_nodes):
+      xlist = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        with torch.no_grad():
+          weights = self.arch_parameters[ self.edge2index[node_str] ]
+          op_name = self.op_names[ weights.argmax().item() ]
+        xlist.append((op_name, j))
+      genotypes.append( tuple(xlist) )
+    return Structure( genotypes )
+
+  def forward(self, inputs):
+    alphas  = nn.functional.softmax(self.arch_parameters, dim=-1)
+
+    feature = self.stem(inputs)
+    for i, cell in enumerate(self.cells):
+      if isinstance(cell, SearchCell):
+        feature = cell(feature, alphas)
+      else:
+        feature = cell(feature)
+
+    out = self.lastact(feature)
+    out = self.global_pooling( out )
+    out = out.view(out.size(0), -1)
+    logits = self.classifier(out)
+
+    return out, logits

lib/models/cell_searchs/search_model_darts_v2.py

@@ -0,0 +1,93 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+########################################################
+# DARTS: Differentiable Architecture Search, ICLR 2019 #
+########################################################
+import torch
+import torch.nn as nn
+from copy import deepcopy
+from ..cell_operations import ResNetBasicblock
+from .search_cells     import SearchCell
+from .genotypes        import Structure
+
+
+class TinyNetworkDartsV2(nn.Module):
+
+  def __init__(self, C, N, max_nodes, num_classes, search_space):
+    super(TinyNetworkDartsV2, self).__init__()
+    self._C        = C
+    self._layerN   = N
+    self.max_nodes = max_nodes
+    self.stem = nn.Sequential(
+                    nn.Conv2d(3, C, kernel_size=3, padding=1, bias=False),
+                    nn.BatchNorm2d(C))
+  
+    layer_channels   = [C    ] * N + [C*2 ] + [C*2  ] * N + [C*4 ] + [C*4  ] * N    
+    layer_reductions = [False] * N + [True] + [False] * N + [True] + [False] * N
+
+    C_prev, num_edge, edge2index = C, None, None
+    self.cells = nn.ModuleList()
+    for index, (C_curr, reduction) in enumerate(zip(layer_channels, layer_reductions)):
+      if reduction:
+        cell = ResNetBasicblock(C_prev, C_curr, 2)
+      else:
+        cell = SearchCell(C_prev, C_curr, 1, max_nodes, search_space)
+        if num_edge is None: num_edge, edge2index = cell.num_edges, cell.edge2index
+        else: assert num_edge == cell.num_edges and edge2index == cell.edge2index, 'invalid {:} vs. {:}.'.format(num_edge, cell.num_edges)
+      self.cells.append( cell )
+      C_prev = cell.out_dim
+    self.op_names   = deepcopy( search_space )
+    self._Layer     = len(self.cells)
+    self.edge2index = edge2index
+    self.lastact    = nn.Sequential(nn.BatchNorm2d(C_prev), nn.ReLU(inplace=True))
+    self.global_pooling = nn.AdaptiveAvgPool2d(1)
+    self.classifier = nn.Linear(C_prev, num_classes)
+    self.arch_parameters = nn.Parameter( 1e-3*torch.randn(num_edge, len(search_space)) )
+
+  def get_weights(self):
+    xlist = list( self.stem.parameters() ) + list( self.cells.parameters() )
+    xlist+= list( self.lastact.parameters() ) + list( self.global_pooling.parameters() )
+    xlist+= list( self.classifier.parameters() )
+    return xlist
+
+  def get_alphas(self):
+    return [self.arch_parameters]
+
+  def get_message(self):
+    string = self.extra_repr()
+    for i, cell in enumerate(self.cells):
+      string += '\n {:02d}/{:02d} :: {:}'.format(i, len(self.cells), cell.extra_repr())
+    return string
+
+  def extra_repr(self):
+    return ('{name}(C={_C}, Max-Nodes={max_nodes}, N={_layerN}, L={_Layer})'.format(name=self.__class__.__name__, **self.__dict__))
+
+  def genotype(self):
+    genotypes = []
+    for i in range(1, self.max_nodes):
+      xlist = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        with torch.no_grad():
+          weights = self.arch_parameters[ self.edge2index[node_str] ]
+          op_name = self.op_names[ weights.argmax().item() ]
+        xlist.append((op_name, j))
+      genotypes.append( tuple(xlist) )
+    return Structure( genotypes )
+
+  def forward(self, inputs):
+    alphas  = nn.functional.softmax(self.arch_parameters, dim=-1)
+
+    feature = self.stem(inputs)
+    for i, cell in enumerate(self.cells):
+      if isinstance(cell, SearchCell):
+        feature = cell(feature, alphas)
+      else:
+        feature = cell(feature)
+
+    out = self.lastact(feature)
+    out = self.global_pooling( out )
+    out = out.view(out.size(0), -1)
+    logits = self.classifier(out)
+
+    return out, logits

lib/models/cell_searchs/search_model_gdas.py

@@ -6,7 +6,7 @@
 import torch
 import torch.nn as nn
 from copy import deepcopy
-from .infer_cells  import ResNetBasicblock
+from ..cell_operations import ResNetBasicblock
 from .search_cells     import SearchCell
 from .genotypes        import Structure
 
@@ -44,7 +44,6 @@ class TinyNetworkGDAS(nn.Module):
     self.classifier = nn.Linear(C_prev, num_classes)
     self.arch_parameters = nn.Parameter( 1e-3*torch.randn(num_edge, len(search_space)) )
     self.tau        = 10
-    self.nan_count  = 0
 
   def get_weights(self):
     xlist = list( self.stem.parameters() ) + list( self.cells.parameters() )
@@ -52,9 +51,8 @@ class TinyNetworkGDAS(nn.Module):
     xlist+= list( self.classifier.parameters() )
     return xlist
 
-  def set_tau(self, tau, _nan_count=0):
+  def set_tau(self, tau):
     self.tau = tau
-    self.nan_count = _nan_count
 
   def get_tau(self):
     return self.tau
@@ -85,27 +83,10 @@ class TinyNetworkGDAS(nn.Module):
     return Structure( genotypes )
 
   def forward(self, inputs):
-    def gumbel_softmax(_logits, _tau):
-      while True: # a trick to avoid the gumbels bug
-        gumbels    = -torch.empty_like(_logits).exponential_().log()
-        new_logits = (_logits.log_softmax(dim=1) + gumbels) / _tau
-        probs      = nn.functional.softmax(new_logits, dim=1)
-        index      = probs.max(-1, keepdim=True)[1]
-        if index[0].item() == self.op_names.index('none') and index[3].item() == self.op_names.index('none') and index[5].item() == self.op_names.index('none'): continue
-        if index[1].item() == self.op_names.index('none') and index[2].item() == self.op_names.index('none') and index[3].item() == self.op_names.index('none') and index[4].item() == self.op_names.index('none'): continue
-        if index[3].item() == self.op_names.index('none') and index[4].item() == self.op_names.index('none') and index[5].item() == self.op_names.index('none'): continue
-        if index[3].item() == self.op_names.index('none') and index[0].item() == self.op_names.index('none') and index[1].item() == self.op_names.index('none'): continue
-        one_h      = torch.zeros_like(_logits).scatter_(-1, index, 1.0)
-        xres       = one_h - probs.detach() + probs
-        if (not torch.isinf(gumbels).any()) and (not torch.isinf(probs).any()) and (not torch.isnan(probs).any()): break
-        self.nan_count += 1
-      return xres, index
-
     feature = self.stem(inputs)
     for i, cell in enumerate(self.cells):
       if isinstance(cell, SearchCell):
-        alphas, IDX  = gumbel_softmax(self.arch_parameters, self.tau)
-        feature = cell.forward_gdas(feature, alphas, IDX.cpu())
+        feature = cell.forward_gdas(feature, self.arch_parameters, self.tau)
       else:
         feature = cell(feature)
 

lib/models/cell_searchs/search_model_setn.py

@@ -0,0 +1,130 @@
+##################################################
+# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019 #
+######################################################################################
+# One-Shot Neural Architecture Search via Self-Evaluated Template Network, ICCV 2019 #
+######################################################################################
+import torch
+import torch.nn as nn
+from copy import deepcopy
+from ..cell_operations import ResNetBasicblock
+from .search_cells     import SearchCell
+from .genotypes        import Structure
+
+
+class TinyNetworkSETN(nn.Module):
+
+  def __init__(self, C, N, max_nodes, num_classes, search_space):
+    super(TinyNetworkSETN, self).__init__()
+    self._C        = C
+    self._layerN   = N
+    self.max_nodes = max_nodes
+    self.stem = nn.Sequential(
+                    nn.Conv2d(3, C, kernel_size=3, padding=1, bias=False),
+                    nn.BatchNorm2d(C))
+  
+    layer_channels   = [C    ] * N + [C*2 ] + [C*2  ] * N + [C*4 ] + [C*4  ] * N    
+    layer_reductions = [False] * N + [True] + [False] * N + [True] + [False] * N
+
+    C_prev, num_edge, edge2index = C, None, None
+    self.cells = nn.ModuleList()
+    for index, (C_curr, reduction) in enumerate(zip(layer_channels, layer_reductions)):
+      if reduction:
+        cell = ResNetBasicblock(C_prev, C_curr, 2)
+      else:
+        cell = SearchCell(C_prev, C_curr, 1, max_nodes, search_space)
+        if num_edge is None: num_edge, edge2index = cell.num_edges, cell.edge2index
+        else: assert num_edge == cell.num_edges and edge2index == cell.edge2index, 'invalid {:} vs. {:}.'.format(num_edge, cell.num_edges)
+      self.cells.append( cell )
+      C_prev = cell.out_dim
+    self.op_names   = deepcopy( search_space )
+    self._Layer     = len(self.cells)
+    self.edge2index = edge2index
+    self.lastact    = nn.Sequential(nn.BatchNorm2d(C_prev), nn.ReLU(inplace=True))
+    self.global_pooling = nn.AdaptiveAvgPool2d(1)
+    self.classifier = nn.Linear(C_prev, num_classes)
+    self.arch_parameters = nn.Parameter( 1e-3*torch.randn(num_edge, len(search_space)) )
+    self.mode       = 'urs'
+    self.dynamic_cell = None
+    
+  def set_cal_mode(self, mode, dynamic_cell=None):
+    assert mode in ['urs', 'joint', 'select', 'dynamic']
+    self.mode = mode
+    if mode == 'dynamic': self.dynamic_cell = deepcopy( dynamic_cell )
+    else                : self.dynamic_cell = None
+
+  def get_cal_mode(self):
+    return self.mode
+
+  def get_weights(self):
+    xlist = list( self.stem.parameters() ) + list( self.cells.parameters() )
+    xlist+= list( self.lastact.parameters() ) + list( self.global_pooling.parameters() )
+    xlist+= list( self.classifier.parameters() )
+    return xlist
+
+  def get_alphas(self):
+    return [self.arch_parameters]
+
+  def get_message(self):
+    string = self.extra_repr()
+    for i, cell in enumerate(self.cells):
+      string += '\n {:02d}/{:02d} :: {:}'.format(i, len(self.cells), cell.extra_repr())
+    return string
+
+  def extra_repr(self):
+    return ('{name}(C={_C}, Max-Nodes={max_nodes}, N={_layerN}, L={_Layer})'.format(name=self.__class__.__name__, **self.__dict__))
+
+  def genotype(self):
+    genotypes = []
+    for i in range(1, self.max_nodes):
+      xlist = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        with torch.no_grad():
+          weights = self.arch_parameters[ self.edge2index[node_str] ]
+          op_name = self.op_names[ weights.argmax().item() ]
+        xlist.append((op_name, j))
+      genotypes.append( tuple(xlist) )
+    return Structure( genotypes )
+
+
+  def dync_genotype(self):
+    genotypes = []
+    with torch.no_grad():
+      alphas_cpu = nn.functional.softmax(self.arch_parameters, dim=-1)
+    for i in range(1, self.max_nodes):
+      xlist = []
+      for j in range(i):
+        node_str = '{:}<-{:}'.format(i, j)
+        weights  = alphas_cpu[ self.edge2index[node_str] ]
+        op_index = torch.multinomial(weights, 1).item()
+        op_name  = self.op_names[ op_index ]
+        xlist.append((op_name, j))
+      genotypes.append( tuple(xlist) )
+    return Structure( genotypes )
+
+
+  def forward(self, inputs):
+    alphas  = nn.functional.softmax(self.arch_parameters, dim=-1)
+    with torch.no_grad():
+      alphas_cpu = alphas.detach().cpu()
+
+    feature = self.stem(inputs)
+    for i, cell in enumerate(self.cells):
+      if isinstance(cell, SearchCell):
+        if self.mode == 'urs':
+          feature = cell.forward_urs(feature)
+        elif self.mode == 'select':
+          feature = cell.forward_select(feature, alphas_cpu)
+        elif self.mode == 'joint':
+          feature = cell.forward_joint(feature, alphas)
+        elif self.mode == 'dynamic':
+          feature = cell.forward_dynamic(feature, self.dynamic_cell)
+        else: raise ValueError('invalid mode={:}'.format(self.mode))
+      else: feature = cell(feature)
+
+    out = self.lastact(feature)
+    out = self.global_pooling( out )
+    out = out.view(out.size(0), -1)
+    logits = self.classifier(out)
+
+    return out, logits

scripts-search/algos/DARTS-V1.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+# bash ./scripts-search/algos/DARTS-V1.sh cifar10 -1
+echo script name: $0
+echo $# arguments
+if [ "$#" -ne 2 ] ;then
+  echo "Input illegal number of parameters " $#
+  echo "Need 2 parameters for dataset and seed"
+  exit 1
+fi
+if [ "$TORCH_HOME" = "" ]; then
+  echo "Must set TORCH_HOME envoriment variable for data dir saving"
+  exit 1
+else
+  echo "TORCH_HOME : $TORCH_HOME"
+fi
+
+dataset=$1
+seed=$2
+channel=16
+num_cells=5
+max_nodes=4
+
+if [ "$dataset" == "cifar10" ] || [ "$dataset" == "cifar100" ]; then
+  data_path="$TORCH_HOME/cifar.python"
+else
+  data_path="$TORCH_HOME/cifar.python/ImageNet16"
+fi
+
+save_dir=./output/cell-search-tiny/DARTS-V1-${dataset}
+
+OMP_NUM_THREADS=4 python ./exps/algos/DARTS-V1.py \
+	--save_dir ${save_dir} --max_nodes ${max_nodes} --channel ${channel} --num_cells ${num_cells} \
+	--dataset ${dataset} --data_path ${data_path} \
+	--search_space_name aa-nas \
+	--arch_learning_rate 0.0003 --arch_weight_decay 0.001 \
+	--workers 4 --print_freq 200 --rand_seed ${seed}

scripts-search/algos/DARTS-V2.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+# bash ./scripts-search/algos/DARTS-V2.sh cifar10 -1
+echo script name: $0
+echo $# arguments
+if [ "$#" -ne 2 ] ;then
+  echo "Input illegal number of parameters " $#
+  echo "Need 2 parameters for dataset and seed"
+  exit 1
+fi
+if [ "$TORCH_HOME" = "" ]; then
+  echo "Must set TORCH_HOME envoriment variable for data dir saving"
+  exit 1
+else
+  echo "TORCH_HOME : $TORCH_HOME"
+fi
+
+dataset=$1
+seed=$2
+channel=16
+num_cells=5
+max_nodes=4
+
+if [ "$dataset" == "cifar10" ] || [ "$dataset" == "cifar100" ]; then
+  data_path="$TORCH_HOME/cifar.python"
+else
+  data_path="$TORCH_HOME/cifar.python/ImageNet16"
+fi
+
+save_dir=./output/cell-search-tiny/DARTS-V2-${dataset}
+
+OMP_NUM_THREADS=4 python ./exps/algos/DARTS-V2.py \
+	--save_dir ${save_dir} --max_nodes ${max_nodes} --channel ${channel} --num_cells ${num_cells} \
+	--dataset ${dataset} --data_path ${data_path} \
+	--search_space_name aa-nas \
+	--arch_learning_rate 0.0003 --arch_weight_decay 0.001 \
+	--workers 4 --print_freq 200 --rand_seed ${seed}

scripts-search/algos/GDAS.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+# bash ./scripts-search/algos/GDAS.sh cifar10 -1
+echo script name: $0
+echo $# arguments
+if [ "$#" -ne 2 ] ;then
+  echo "Input illegal number of parameters " $#
+  echo "Need 2 parameters for dataset and seed"
+  exit 1
+fi
+if [ "$TORCH_HOME" = "" ]; then
+  echo "Must set TORCH_HOME envoriment variable for data dir saving"
+  exit 1
+else
+  echo "TORCH_HOME : $TORCH_HOME"
+fi
+
+dataset=$1
+seed=$2
+channel=16
+num_cells=5
+max_nodes=4
+
+if [ "$dataset" == "cifar10" ] || [ "$dataset" == "cifar100" ]; then
+  data_path="$TORCH_HOME/cifar.python"
+else
+  data_path="$TORCH_HOME/cifar.python/ImageNet16"
+fi
+
+save_dir=./output/cell-search-tiny/GDAS-${dataset}
+
+OMP_NUM_THREADS=4 python ./exps/algos/GDAS.py \
+	--save_dir ${save_dir} --max_nodes ${max_nodes} --channel ${channel} --num_cells ${num_cells} \
+	--dataset ${dataset} --data_path ${data_path} \
+	--search_space_name aa-nas \
+	--tau_max 10 --tau_min 0.1 \
+	--arch_learning_rate 0.0003 --arch_weight_decay 0.001 \
+	--workers 4 --print_freq 200 --rand_seed ${seed}

scripts-search/algos/SETN.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+# One-Shot Neural Architecture Search via Self-Evaluated Template Network, ICCV 2019
+# bash ./scripts-search/scripts/algos/SETN.sh cifar10 -1
+echo script name: $0
+echo $# arguments
+if [ "$#" -ne 2 ] ;then
+  echo "Input illegal number of parameters " $#
+  echo "Need 2 parameters for dataset and seed"
+  exit 1
+fi
+if [ "$TORCH_HOME" = "" ]; then
+  echo "Must set TORCH_HOME envoriment variable for data dir saving"
+  exit 1
+else
+  echo "TORCH_HOME : $TORCH_HOME"
+fi
+
+dataset=$1
+seed=$2
+channel=16
+num_cells=5
+max_nodes=4
+
+if [ "$dataset" == "cifar10" ] || [ "$dataset" == "cifar100" ]; then
+  data_path="$TORCH_HOME/cifar.python"
+else
+  data_path="$TORCH_HOME/cifar.python/ImageNet16"
+fi
+
+save_dir=./output/cell-search-tiny/SETN-${dataset}
+
+OMP_NUM_THREADS=4 python ./exps/algos/SETN.py \
+	--save_dir ${save_dir} --max_nodes ${max_nodes} --channel ${channel} --num_cells ${num_cells} \
+	--dataset ${dataset} --data_path ${data_path} \
+	--search_space_name aa-nas \
+	--arch_learning_rate 0.0003 --arch_weight_decay 0.001 \
+	--select_num 100 \
+	--workers 4 --print_freq 200 --rand_seed ${seed}