Python tqdm show progress bar

tqdm can help to show a smart progress bar, and it is very easy to use, just wrap any iterable with tqdm(iterable), and you’re done!

the best way to learn is to read the official document: https://pypi.python.org/pypi/tqdm

i just copy the documents and add part of my understand.

Interable-based

Wrap tqdm() around any iterable:

text = ""
for char in tqdm(["a", "b", "c", "d"]):
    text = text + char

trange(i) is a special optimised instance of tqdm(range(i)):

for i in trange(100):
    pass

Instantiation outside of the loop allows for manual control over tqdm():

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

Manual

Manual control on tqdm() updates by using a with statement:

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

If the optional variable total (or an iterable with len()) is provided, predictive stats are displayed.

with is also optional (you can just assign tqdm() to a variable, but in this case don’t forget to del or close() at the end:

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

Parameters

there are other parameters to give detail settings.

class tqdm(object):
  """
  Decorate an iterable object, returning an iterator which acts exactly
  like the original iterable, but prints a dynamically updating
  progressbar every time a value is requested.
  """

  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,
               postfix=None):