Python Tips (my memo)

important point

It is for myself only. We hope for your reference.
If you want to add it yourself, I will do it at any time.
There is a better way! In that case, I would like advice.
The version written in each item is the version of Python that I have confirmed the operation. Other than that, I don't know if it works.

Handle files under the directory

2.7.10

To read all files under "/ path / to".

import glob

for file in glob.glob('/path/to/*'):

  f = open(file, 'r')
  
  for line in f.readlines():
    print line
    
  f.close()

Get datetime for this Monday and Sunday

2.6.6

import datetime

today = datetime.datetime.today()

this_monday = today - datetime.timedelta(today.weekday())
this_sunday = today + datetime.timedelta(6 - today.weekday())

print 'Today: ' + today.ctime()
print 'Monay: ' + this_monday.ctime()
print 'Sunday: ' + this_sunday.ctime()

Result

Today: Fri Jun 19 13:20:59 2015
Monay: Mon Jun 15 13:20:59 2015
Sunday: Sun Jun 21 13:20:59 2015

Fill with 0 when returning a numeric type to a character string type

2.6.6

For example, convert a 1-digit number to a 4-digit character string and fill the left with 0.

num = 1

('0' * 4 + str(num))[-4:]

Result

'0001'

Create a dictionary / dictionary from two lists

2.6.6

>>> a = ['a', 'b', 'c']
>>> b = [1,2,3]
>>> dict(zip(a,b))
{'a': 1, 'c': 3, 'b': 2}

Sort by key when converting dictionary type to json in json library

2.6.6

in json.dump

sort_keys=True

Just pass.

>>> import json
>>>
>>> d = {'b':1, 'a':2, 'c':3}
>>>
>>> json.dumps(d)
'{"a": 2, "c": 3, "b": 1}'
>>>
>>> json.dumps(d, sort_keys=True)
'{"a": 2, "b": 1, "c": 3}'
>>>

Convert comma-separated numeric strings to numbers

2.6.6

Remove the comma with replace.

>>> '5,007,167,488'.replace(',','')
'5007167488'
>>> int('5,007,167,488'.replace(',',''))
5007167488