python的Tqdm模块的使用

Tqdm 是一个快速，可扩展的Python进度条，可以在 Python 长循环中添加一个进度提示信息，用户只需要封装任意的迭代器 tqdm(iterator)。

我的系统是window环境，首先安装python，接下来就是pip。

pip安装：

在python根目录下创建一个get-pip.py的文件，内容：

https://bootstrap.pypa.io/get-pip.py

然后在CMD窗口进入python下面：

输出：

python -m pip install -U pip 

由于Tqdm要求的pip版本是9.0所以需要手动安装pip9.0
http://pypi.python.org/pypi/pip

下载安装包9.0

然后解压进入，CMD窗口输入：python setup.py install

然后就可以安装Tqdm了，

pip install tqdm 

安装最新的开发版的话

pip install -e git+https://github.com/tqdm/tqdm.git@master#egg=tqdm 

最后看看怎么用呢？https://pypi.python.org/pypi/tqdm

基本用法：

from tqdm import tqdm
for i in tqdm(range(10000)):
   sleep(0.01)

当然除了tqdm，还有trange,使用方式完全相同

for i in trange(100):
    sleep(0.1)

只要传入list都可以：

pbar = tqdm(["a", "b", "c", "d"])
for char in pbar:
  pbar.set_description("Processing %s" % char) 

也可以手动控制更新

with tqdm(total=100) as pbar:
  for i in range(10):
    pbar.update(10)

也可以这样：

pbar = tqdm(total=100)
for i in range(10):
  pbar.update(10)
pbar.close()

在Shell的tqdm用法

统计所有python脚本的行数：

$ time find . -name '*.py' -exec cat \{} \; | wc -l
857365 

real  0m3.458s
user  0m0.274s
sys   0m3.325s 

$ time find . -name '*.py' -exec cat \{} \; | tqdm | wc -l
857366it [00:03, 246471.31it/s]
857365 

real  0m3.585s
user  0m0.862s
sys   0m3.358s 

使用参数：

$ find . -name '*.py' -exec cat \{} \; |
  tqdm --unit loc --unit_scale --total 857366 >> /dev/null
100%|███████████████████████████████████| 857K/857K [00:04<00:00, 246Kloc/s] 

备份一个目录：

$ 7z a -bd -r backup.7z docs/ | grep Compressing |
  tqdm --total $(find docs/ -type f | wc -l) --unit files >> backup.log
100%|███████████████████████████████▉| 8014/8014 [01:37<00:00, 82.29files/s] 

通过看示范的代码，我们能发现使用的核心是tqdm和trange这两个函数，从代码层面分析tqdm的功能，那首先是init.py

__all__ = ['tqdm', 'tqdm_gui', 'trange', 'tgrange', 'tqdm_pandas',
      'tqdm_notebook', 'tnrange', 'main', 'TqdmKeyError', 'TqdmTypeError',
      '__version__'] 

跟踪到_tqdm.py，能看到tqdm类的声明，首先是初始化

def __init__(self, iterable=None, desc=None, total=None, leave=True,
         file=sys.stderr, ncols=None, mininterval=0.1,
         maxinterval=10.0, miniters=None, ascii=None, disable=False,
         unit='it', unit_scale=False, dynamic_ncols=False,
         smoothing=0.3, bar_format=None, initial=0, position=None,
         gui=False, **kwargs): 

Parameters 

iterable : iterable, optional
Iterable to decorate with a progressbar.
可迭代的进度条。
Leave blank to manually manage the updates.
留空手动管理更新？？
desc : str, optional
Prefix for the progressbar.
进度条的描述
total : int, optional
The number of expected iterations. If unspecified,
len(iterable) is used if possible. As a last resort, only basic
progress statistics are displayed (no ETA, no progressbar).
If gui is True and this parameter needs subsequent updating,
specify an initial arbitrary large positive integer,
e.g. int(9e9).
预期的迭代数目，默认为None，则尽可能的迭代下去，如果gui设置为True，这里则需要后续的更新，将需要指定为一个初始随意值较大的正整数，例如int(9e9)
leave : bool, optional
If [default: True], keeps all traces of the progressbar
upon termination of iteration.
保留进度条存在的痕迹，简单来说就是会把进度条的最终形态保留下来，默认为True
file : io.TextIOWrapper or io.StringIO, optional
Specifies where to output the progress messages
[default: sys.stderr]. Uses file.write(str) and file.flush()
methods.
指定消息的输出
ncols : int, optional
The width of the entire output message. If specified,
dynamically resizes the progressbar to stay within this bound.
If unspecified, attempts to use environment width. The
fallback is a meter width of 10 and no limit for the counter and
statistics. If 0, will not print any meter (only stats).
整个输出消息的宽度。如果指定，动态调整的进度停留在这个边界。如果未指定，尝试使用环境的宽度。如果为0，将不打印任何东西（只统计）。
mininterval : float, optional
Minimum progress update interval, in seconds [default: 0.1].
最小进度更新间隔，以秒为单位（默认值：0.1）。
maxinterval : float, optional
Maximum progress update interval, in seconds [default: 10.0].
最大进度更新间隔，以秒为单位（默认值：10）。
miniters : int, optional
Minimum progress update interval, in iterations.
If specified, will set mininterval to 0.
最小进度更新周期
ascii : bool, optional
If unspecified or False, use unicode (smooth blocks) to fill
the meter. The fallback is to use ASCII characters 1-9 #.
如果不设置，默认为unicode编码
disable : bool, optional
Whether to disable the entire progressbar wrapper
[default: False].
是否禁用整个进度条包装(如果为True，进度条不显示)
unit : str, optional
String that will be used to define the unit of each iteration
[default: it].
将被用来定义每个单元的字符串？？？
unit_scale : bool, optional
If set, the number of iterations will be reduced/scaled
automatically and a metric prefix following the
International System of Units standard will be added
(kilo, mega, etc.) [default: False].
如果设置，迭代的次数会自动按照十、百、千来添加前缀，默认为false
dynamic_ncols : bool, optional
If set, constantly alters ncols to the environment (allowing
for window resizes) [default: False].
不断改变ncols环境，允许调整窗口大小
smoothing : float, optional
Exponential moving average smoothing factor for speed estimates
(ignored in GUI mode). Ranges from 0 (average speed) to 1
(current/instantaneous speed) [default: 0.3]. 

bar_format : str, optional
Specify a custom bar string formatting. May impact performance.
If unspecified, will use ‘{l_bar}{bar}{r_bar}', where l_bar is
‘{desc}{percentage:3.0f}%|' and r_bar is
‘| {n_fmt}/{total_fmt} [{elapsed_str}<{remaining_str}, {rate_fmt}]'
Possible vars: bar, n, n_fmt, total, total_fmt, percentage,
rate, rate_fmt, elapsed, remaining, l_bar, r_bar, desc.
自定义栏字符串格式化…默认会使用{l_bar}{bar}{r_bar}的格式，格式同上 

initial : int, optional
The initial counter value. Useful when restarting a progress
bar [default: 0].
初始计数器值，默认为0
position : int, optional
Specify the line offset to print this bar (starting from 0)
Automatic if unspecified.
Useful to manage multiple bars at once (eg, from threads).
指定偏移，这个功能在多个条中有用
gui : bool, optional
WARNING: internal parameter - do not use.
Use tqdm_gui(…) instead. If set, will attempt to use
matplotlib animations for a graphical output [default: False].
内部参数…
Returns
out : decorated iterator.
返回为一个迭代器 

其实不用分析更多代码，多看看几个例子：(官网的例子)

7zx.py压缩进度条

# -*- coding: utf-8 -*-
"""Usage:
 7zx.py [--help | options] <zipfiles>...
Options:
 -h, --help   Print this help and exit
 -v, --version Print version and exit
 -c, --compressed    Use compressed (instead of uncompressed) file sizes
 -s, --silent  Do not print one row per zip file
 -y, --yes   Assume yes to all queries (for extraction)
 -D=<level>, --debug=<level>
         Print various types of debugging information. Choices:
             CRITICAL|FATAL
             ERROR
             WARN(ING)
             [default: INFO]
             DEBUG
             NOTSET
 -d, --debug-trace   Print lots of debugging information (-D NOTSET)
"""
from __future__ import print_function
from docopt import docopt
import logging as log
import subprocess
import re
from tqdm import tqdm
import pty
import os
import io
__author__ = "Casper da Costa-Luis <casper.dcl@physics.org>"
__licence__ = "MPLv2.0"
__version__ = "0.2.0"
__license__ = __licence__ 

RE_SCN = re.compile("([0-9]+)\s+([0-9]+)\s+(.*)$", flags=re.M) 

def main():
  args = docopt(__doc__, version=__version__)
  if args.pop('--debug-trace', False):
    args['--debug'] = "NOTSET"
  log.basicConfig(level=getattr(log, args['--debug'], log.INFO),
          format='%(levelname)s: %(message)s')
  log.debug(args) 

  # Get compressed sizes
  zips = {}
  for fn in args['<zipfiles>']:
    info = subprocess.check_output(["7z", "l", fn]).strip()
    finfo = RE_SCN.findall(info) 

    # builtin test: last line should be total sizes
    log.debug(finfo)
    totals = map(int, finfo[-1][:2])
    # log.debug(totals)
    for s in range(2):
      assert(sum(map(int, (inf[s] for inf in finfo[:-1]))) == totals[s])
    fcomp = dict((n, int(c if args['--compressed'] else u))
           for (u, c, n) in finfo[:-1])
    # log.debug(fcomp)
    # zips : {'zipname' : {'filename' : int(size)}}
    zips[fn] = fcomp 

  # Extract
  cmd7zx = ["7z", "x", "-bd"]
  if args['--yes']:
    cmd7zx += ["-y"]
  log.info("Extracting from {:d} file(s)".format(len(zips)))
  with tqdm(total=sum(sum(fcomp.values()) for fcomp in zips.values()),
       unit="B", unit_scale=True) as tall:
    for fn, fcomp in zips.items():
      md, sd = pty.openpty()
      ex = subprocess.Popen(cmd7zx + [fn],
                 bufsize=1,
                 stdout=md, # subprocess.PIPE,
                 stderr=subprocess.STDOUT)
      os.close(sd)
      with io.open(md, mode="rU", buffering=1) as m:
        with tqdm(total=sum(fcomp.values()), disable=len(zips) < 2,
             leave=False, unit="B", unit_scale=True) as t:
          while True:
            try:
              l_raw = m.readline()
            except IOError:
              break
            l = l_raw.strip()
            if l.startswith("Extracting"):
              exname = l.lstrip("Extracting").lstrip()
              s = fcomp.get(exname, 0) # 0 is likely folders
              t.update(s)
              tall.update(s)
            elif l:
              if not any(l.startswith(i) for i in
                    ("7-Zip ",
                    "p7zip Version ",
                    "Everything is Ok",
                    "Folders: ",
                    "Files: ",
                    "Size: ",
                    "Compressed: ")):
                if l.startswith("Processing archive: "):
                  if not args['--silent']:
                    t.write(t.format_interval(
                      t.start_t - tall.start_t) + ' ' +
                      l.lstrip("Processing archive: "))
                else:
                  t.write(l)
      ex.wait() 

main.__doc__ = __doc__ 

if __name__ == "__main__":
  main() 

tqdm_wget.py

"""An example of wrapping manual tqdm updates for urllib reporthook.
# urllib.urlretrieve documentation
> If present, the hook function will be called once
> on establishment of the network connection and once after each block read
> thereafter. The hook will be passed three arguments; a count of blocks
> transferred so far, a block size in bytes, and the total size of the file.
Usage:
  tqdm_wget.py [options]
Options:
-h, --help
  Print this help message and exit
-u URL, --url URL : string, optional
  The url to fetch.
  [default: http://www.doc.ic.ac.uk/~cod11/matryoshka.zip]
-o FILE, --output FILE : string, optional
  The local file path in which to save the url [default: /dev/null].
""" 

import urllib
from tqdm import tqdm
from docopt import docopt 

def my_hook(t):
  """
  Wraps tqdm instance. Don't forget to close() or __exit__()
  the tqdm instance once you're done with it (easiest using `with` syntax).
  Example
  -------
  >>> with tqdm(...) as t:
  ...   reporthook = my_hook(t)
  ...   urllib.urlretrieve(..., reporthook=reporthook)
  """
  last_b = [0] 

  def inner(b=1, bsize=1, tsize=None):
    """
    b : int, optional
      Number of blocks just transferred [default: 1].
    bsize : int, optional
      Size of each block (in tqdm units) [default: 1].
    tsize : int, optional
      Total size (in tqdm units). If [default: None] remains unchanged.
    """
    if tsize is not None:
      t.total = tsize
    t.update((b - last_b[0]) * bsize)
    last_b[0] = b
  return inner 

opts = docopt(__doc__) 

eg_link = opts['--url']
eg_file = eg_link.replace('/', ' ').split()[-1]
with tqdm(unit='B', unit_scale=True, leave=True, miniters=1,
     desc=eg_file) as t: # all optional kwargs
  urllib.urlretrieve(eg_link, filename=opts['--output'],
            reporthook=my_hook(t), data=None) 

examples.py

"""
# Simple tqdm examples and profiling
# Benchmark
for i in _range(int(1e8)):
  pass
# Basic demo
import tqdm
for i in tqdm.trange(int(1e8)):
  pass
# Some decorations
import tqdm
for i in tqdm.trange(int(1e8), miniters=int(1e6), ascii=True,
           desc="cool", dynamic_ncols=True):
  pass
# Nested bars
from tqdm import trange
for i in trange(10):
  for j in trange(int(1e7), leave=False, unit_scale=True):
    pass
# Experimental GUI demo
import tqdm
for i in tqdm.tgrange(int(1e8)):
  pass
# Comparison to https://code.google.com/p/python-progressbar/
try:
  from progressbar.progressbar import ProgressBar
except ImportError:
  pass
else:
  for i in ProgressBar()(_range(int(1e8))):
    pass
# Dynamic miniters benchmark
from tqdm import trange
for i in trange(int(1e8), miniters=None, mininterval=0.1, smoothing=0):
  pass
# Fixed miniters benchmark
from tqdm import trange
for i in trange(int(1e8), miniters=4500000, mininterval=0.1, smoothing=0):
  pass
""" 

from time import sleep
from timeit import timeit
import re 

# Simple demo
from tqdm import trange
for i in trange(16, leave=True):
  sleep(0.1) 

# Profiling/overhead tests
stmts = filter(None, re.split(r'\n\s*#.*?\n', __doc__))
for s in stmts:
  print(s.replace('import tqdm\n', ''))
  print(timeit(stmt='try:\n\t_range = xrange'
           '\nexcept:\n\t_range = range\n' + s, number=1),
     'seconds')

pandas_progress_apply.py

import pandas as pd
import numpy as np
from tqdm import tqdm 

df = pd.DataFrame(np.random.randint(0, 100, (100000, 6))) 

# Register `pandas.progress_apply` and `pandas.Series.map_apply` with `tqdm`
# (can use `tqdm_gui`, `tqdm_notebook`, optional kwargs, etc.)
tqdm.pandas(desc="my bar!") 

# Now you can use `progress_apply` instead of `apply`
# and `progress_map` instead of `map`
df.progress_apply(lambda x: x**2)
# can also groupby:
# df.groupby(0).progress_apply(lambda x: x**2) 

# -- Source code for `tqdm_pandas` (really simple!)
# def tqdm_pandas(t):
#  from pandas.core.frame import DataFrame
#  def inner(df, func, *args, **kwargs):
#    t.total = groups.size // len(groups)
#    def wrapper(*args, **kwargs):
#      t.update(1)
#      return func(*args, **kwargs)
#    result = df.apply(wrapper, *args, **kwargs)
#    t.close()
#    return result
#  DataFrame.progress_apply = inner

引用tqdm并非强制作为依赖：

include_no_requirements.py

# How to import tqdm without enforcing it as a dependency
try:
  from tqdm import tqdm
except ImportError:
  def tqdm(*args, **kwargs):
    if args:
      return args[0]
    return kwargs.get('iterable', None)

参考：
https://github.com/tqdm/tqdm/tree/master/examples
https://pypi.python.org/pypi/tqdm
https://github.com/tqdm/tqdm

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。