python training progress bar

progress_bar.py

import time
import os
import sys

term_width = 148

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()
    
    cur_len = int(TOTAL_BAR_LENGTH * current / total)
    rest_len = int(TOTAL_BAR_LENGTH - current）- 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 # 每一步的计算时间
    last_time = cur_time
    tot_time = cur_time - begin_time # 总共的计算时间

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

    msg = ''.join(L)
    sys.stdout.write(msg)
    # 剩下的部分写入空格
    for i in range(term_width - int(TOTAL_BAR_LENGTH) - len(msg) - 3):
        sys.stdout.write(' ')
    
    # 移动光标到 progress bar 的中央
    for i in range(term_width - (TOTAL_BAR_LENGTH / 2) + 2):
        sys.stdout.write('\b')
    
    # 写入当前进度
    sys.stdout.write(' %d/%d ' % (current+1, total))

    # 如果当前的 current 值还没有达到 total，那么将当前光标移动到行首
    # 本次 progress_bar 调用结束 
    # 下一次，main 程序中将会传递个新的 current 值，重新调用 progrss_bar，还是在当前行显示进度
    # 如果 current 已经到达 total 值，那么将会换行，下一次 main 中调用时，就会在新行显示进度
    if current < total - 1:
        sys.stdout.write('\r')
    else:
        sys.stdout.write('\n')
    
    # 每轮调用结束需要在控制台中刷新
    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