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# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019.08 #
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# python exps/NAS-Bench-201/check.py --base_save_dir 
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import os, sys, time, argparse, collections
from shutil import copyfile
import torch
import torch.nn as nn
from pathlib import Path
from collections import defaultdict
lib_dir = (Path(__file__).parent / '..' / '..' / 'lib').resolve()
if str(lib_dir) not in sys.path: sys.path.insert(0, str(lib_dir))
from log_utils    import AverageMeter, time_string, convert_secs2time


def check_files(save_dir, meta_file, basestr):
  meta_infos     = torch.load(meta_file, map_location='cpu')
  meta_archs     = meta_infos['archs']
  meta_num_archs = meta_infos['total']
  meta_max_node  = meta_infos['max_node']
  assert meta_num_archs == len(meta_archs), 'invalid number of archs : {:} vs {:}'.format(meta_num_archs, len(meta_archs))

  sub_model_dirs = sorted(list(save_dir.glob('*-*-{:}'.format(basestr))))
  print ('{:} find {:} directories used to save checkpoints'.format(time_string(), len(sub_model_dirs)))
  
  subdir2archs, num_evaluated_arch = collections.OrderedDict(), 0
  num_seeds = defaultdict(lambda: 0)
  for index, sub_dir in enumerate(sub_model_dirs):
    xcheckpoints = list(sub_dir.glob('arch-*-seed-*.pth'))
    #xcheckpoints = list(sub_dir.glob('arch-*-seed-0777.pth')) + list(sub_dir.glob('arch-*-seed-0888.pth')) + list(sub_dir.glob('arch-*-seed-0999.pth'))
    arch_indexes = set()
    for checkpoint in xcheckpoints:
      temp_names = checkpoint.name.split('-')
      assert len(temp_names) == 4 and temp_names[0] == 'arch' and temp_names[2] == 'seed', 'invalid checkpoint name : {:}'.format(checkpoint.name)
      arch_indexes.add( temp_names[1] )
    subdir2archs[sub_dir] = sorted(list(arch_indexes))
    num_evaluated_arch   += len(arch_indexes)
    # count number of seeds for each architecture
    for arch_index in arch_indexes:
      num_seeds[ len(list(sub_dir.glob('arch-{:}-seed-*.pth'.format(arch_index)))) ] += 1
  print('There are {:5d} architectures that have been evaluated ({:} in total, {:} ckps in total).'.format(num_evaluated_arch, meta_num_archs, sum(k*v for k, v in num_seeds.items())))
  for key in sorted( list( num_seeds.keys() ) ): print ('There are {:5d} architectures that are evaluated {:} times.'.format(num_seeds[key], key))

  dir2ckps, dir2ckp_exists = dict(), dict()
  start_time, epoch_time = time.time(), AverageMeter()
  for IDX, (sub_dir, arch_indexes) in enumerate(subdir2archs.items()):
    seeds = [777, 888, 999]
    numrs = defaultdict(lambda: 0)
    all_checkpoints, all_ckp_exists = [], []
    for arch_index in arch_indexes:
      checkpoints = ['arch-{:}-seed-{:04d}.pth'.format(arch_index, seed) for seed in seeds]
      ckp_exists  = [(sub_dir/x).exists() for x in checkpoints]
      arch_index  = int(arch_index)
      assert 0 <= arch_index < len(meta_archs), 'invalid arch-index {:} (not found in meta_archs)'.format(arch_index)
      all_checkpoints += checkpoints
      all_ckp_exists  += ckp_exists
      numrs[sum(ckp_exists)] += 1
    dir2ckps[ str(sub_dir) ]       = all_checkpoints
    dir2ckp_exists[ str(sub_dir) ] = all_ckp_exists
    # measure time
    epoch_time.update(time.time() - start_time)
    start_time = time.time()
    numrstr = ', '.join( ['{:}: {:03d}'.format(x, numrs[x]) for x in sorted(numrs.keys())] )
    print('{:} load [{:2d}/{:2d}] [{:03d} archs] [{:04d}->{:04d} ckps] {:} done, need {:}. {:}'.format(time_string(), IDX+1, len(subdir2archs), len(arch_indexes), len(all_checkpoints), sum(all_ckp_exists), sub_dir, convert_secs2time(epoch_time.avg * (len(subdir2archs)-IDX-1), True), numrstr))


if __name__ == '__main__':

  parser = argparse.ArgumentParser(description='NAS Benchmark 201', formatter_class=argparse.ArgumentDefaultsHelpFormatter)
  parser.add_argument('--base_save_dir',  type=str, default='./output/NAS-BENCH-201-4',     help='The base-name of folder to save checkpoints and log.')
  parser.add_argument('--max_node',       type=int, default=4,                                 help='The maximum node in a cell.')
  parser.add_argument('--channel',        type=int, default=16,                                help='The number of channels.')
  parser.add_argument('--num_cells',      type=int, default=5,                                 help='The number of cells in one stage.')
  args = parser.parse_args()
  
  save_dir  = Path( args.base_save_dir )
  meta_path = save_dir / 'meta-node-{:}.pth'.format(args.max_node)
  assert save_dir.exists(),  'invalid save dir path : {:}'.format(save_dir)
  assert meta_path.exists(), 'invalid saved meta path : {:}'.format(meta_path)
  print ('check NAS-Bench-201 in {:}'.format(save_dir))

  basestr = 'C{:}-N{:}'.format(args.channel, args.num_cells)
  check_files(save_dir, meta_path, basestr)