utils.py

'''Some helper functions for PyTorch, including:
    - get_mean_and_std: calculate the mean and std value of dataset.
    - msr_init: net parameter initialization.
    - progress_bar: progress bar mimic xlua.progress.
'''
import os
import sys
import time
import math

import torch.nn as nn
import torch.nn.init as init
import logging.config
import torch

def setup_logging(log_file='log.txt'):
    """Setup logging configuration
    """
    logging.basicConfig(level=logging.DEBUG,
                        format="%(asctime)s - %(levelname)s - %(message)s",
                        datefmt="%Y-%m-%d %H:%M:%S",
                        filename=log_file,
                        filemode='w')
    console = logging.StreamHandler()
    console.setLevel(logging.INFO)
    formatter = logging.Formatter('%(message)s')
    console.setFormatter(formatter)
    logging.getLogger('').addHandler(console)

__optimizers = {
    'SGD': torch.optim.SGD,
    'ASGD': torch.optim.ASGD,
    'Adam': torch.optim.Adam,
    'Adamax': torch.optim.Adamax,
    'Adagrad': torch.optim.Adagrad,
    'Adadelta': torch.optim.Adadelta,
    'Rprop': torch.optim.Rprop,
    'RMSprop': torch.optim.RMSprop
}

def adjust_optimizer(optimizer, epoch, config):
    """Reconfigures the optimizer according to epoch and config dict"""
    def modify_optimizer(optimizer, setting):
        if 'optimizer' in setting:
            optimizer = __optimizers[setting['optimizer']](
                optimizer.param_groups)
            logging.info('OPTIMIZER - setting method = %s' %
                          setting['optimizer'])
        for param_group in optimizer.param_groups:
            for key in param_group.keys():
                if key in setting:
                    logging.info('OPTIMIZER - setting %s = %s' %
                                  (key, setting[key]))
                    param_group[key] = setting[key]
        return optimizer

    if callable(config):
        optimizer = modify_optimizer(optimizer, config(epoch))
    else:
        for e in range(epoch + 1):  # run over all epochs - sticky setting
            if e in config:
                optimizer = modify_optimizer(optimizer, config[e])

    return optimizer

def get_mean_and_std(dataset):
    '''Compute the mean and std value of dataset.'''
    dataloader = torch.utils.data.DataLoader(dataset, batch_size=1, shuffle=True, num_workers=2)
    mean = torch.zeros(3)
    std = torch.zeros(3)
    print('==> Computing mean and std..')
    for inputs, targets in dataloader:
        for i in range(3):
            mean[i] += inputs[:,i,:,:].mean()
            std[i] += inputs[:,i,:,:].std()
    mean.div_(len(dataset))
    std.div_(len(dataset))
    return mean, std

def init_params(net):
    '''Init layer parameters.'''
    for m in net.modules():
        if isinstance(m, nn.Conv2d):
            init.kaiming_normal(m.weight, mode='fan_out')
            if m.bias:
                init.constant(m.bias, 0)
        elif isinstance(m, nn.BatchNorm2d):
            init.constant(m.weight, 1)
            init.constant(m.bias, 0)
        elif isinstance(m, nn.Linear):
            init.normal(m.weight, std=1e-3)
            if m.bias:
                init.constant(m.bias, 0)


# _, term_width = os.popen('stty size', 'r').read().split()
# term_width = int(term_width)

# TOTAL_BAR_LENGTH = 65.
# last_time = time.time()
# begin_time = last_time
def progress_bar(current, total, msg=None):
    global last_time, begin_time
    if current == 0:
        begin_time = time.time()  # Reset for new bar.

    cur_len = int(TOTAL_BAR_LENGTH*current/total)
    rest_len = int(TOTAL_BAR_LENGTH - cur_len) - 1

    sys.stdout.write(' [')
    for i in range(cur_len):
        sys.stdout.write('=')
    sys.stdout.write('>')
    for i in range(rest_len):
        sys.stdout.write('.')
    sys.stdout.write(']')

    cur_time = time.time()
    step_time = cur_time - last_time
    last_time = cur_time
    tot_time = cur_time - begin_time

    L = []
    L.append('  Step: %s' % format_time(step_time))
    L.append(' | Tot: %s' % format_time(tot_time))
    if msg:
        L.append(' | ' + msg)

    msg = ''.join(L)
    sys.stdout.write(msg)
    for i in range(term_width-int(TOTAL_BAR_LENGTH)-len(msg)-3):
        sys.stdout.write(' ')

    # Go back to the center of the bar.
    for i in range(term_width-int(TOTAL_BAR_LENGTH/2)+2):
        sys.stdout.write('\b')
    sys.stdout.write(' %d/%d ' % (current+1, total))

    if current < total-1:
        sys.stdout.write('\r')
    else:
        sys.stdout.write('\n')
    sys.stdout.flush()

def format_time(seconds):
    days = int(seconds / 3600/24)
    seconds = seconds - days*3600*24
    hours = int(seconds / 3600)
    seconds = seconds - hours*3600
    minutes = int(seconds / 60)
    seconds = seconds - minutes*60
    secondsf = int(seconds)
    seconds = seconds - secondsf
    millis = int(seconds*1000)

    f = ''
    i = 1
    if days > 0:
        f += str(days) + 'D'
        i += 1
    if hours > 0 and i <= 2:
        f += str(hours) + 'h'
        i += 1
    if minutes > 0 and i <= 2:
        f += str(minutes) + 'm'
        i += 1
    if secondsf > 0 and i <= 2:
        f += str(secondsf) + 's'
        i += 1
    if millis > 0 and i <= 2:
        f += str(millis) + 'ms'
        i += 1
    if f == '':
        f = '0ms'
    return f