""" This is a brief standard library test case for python """

if __name__ == "__main__":

# Operating System Interface

import os

# os.system('command') to execute the native command, return 0 means success while 1 mean failure.

os.system('dir jiaweizhang111')

print os.getcwd()

os.chdir('.')

print os.getcwd()

# According to daily file and dictionary management task, the shutil a higher level interface that is eaiser to use.

import shutil

shutil.copyfile('data', 'data1')

shutil.move('data1', 'data')

# glob module for making lists from directory wildcard searches.

import glob

print glob.glob('*.py')

# standard error, standard out, standard in and terminate program

import sys

sys.stderr.write('stderr')

print

sys.stdout.write('stdout')

print

# print sys.stdin.readline() # input a line from keyboard.

# print sys.stdin.readlines() # input mutipule lines from keyboard, ctrl-z to break.

# sys.exit(0) # exit program with successful status.

# String pattern matching

import re

print re.findall('\\bf[a-z]*', 'which afoot foot or hand fell fastest')

# equals to because of \b here, afoot will not be shown.

print re.findall(r'\bf[a-z]*', 'which afoot foot or hand fell fastest')

print re.sub(r'(\b[a-z]+) \1', r'\1', 'cat in the the hat')

print 'one too three'.replace('too', 'two')

# mathematics

import math

print math.sin(math.pi / 2)

print math.log(1024, 2)

import random

print random.choice(['apple', 'pear', 'banana'])

print random.sample(range(100), 10)

print random.random()

print random.randrange(6)

# internet access

import urllib2

for line in urllib2.urlopen('http://www.baidu.com'):

if 'style=height:60px' in line:

print line

# comment the codes below since it needs a mailserver running on localhost, 'sudo apt-get install sendmail' if you want to run a mail server locally.

# import smtplib

# server = smtplib.SMTP('localhost')

# server.sendmail(...)

# server.quit()

# download file.

# import urllib

# urllib.urlretrieve('http://haoetv.com/haoting/wma08/318.wma', 'C:\\318.wma')

# Date time

from datetime import date

now = date.today()

print now.strftime("%m-%d-%y. %d %b %Y is a %A on the %d day of %B.") # same to: import time && print time.strftime('%d%b%y')

birthday = date(1980, 11, 14)

age = now - birthday

print age.days

# archiving and compression data, other module including zlib, gzip, bz2, zipfile, tarfile

import zlib

s = 'The datas will be archived and compressed.'

print 'The length of data before compression: {0}'.format(len(s))

t = zlib.compress(s)

print 'The length of data after compression: {0}'.format(len(t))

s = zlib.decompress(t)

print 'The length of data after decompression: {0}'.format(len(s))

# performance measurement, other module to test performace including profile and pstats

import timeit

print timeit.Timer('t = a; a = b; b = t', 'a = 1; b = 2').timeit()

print timeit.Timer('a, b = b, a', 'a = 1; b = 2').timeit()

# unit test, doctest and unittest module for unit test.

def average(values):

"""Computing average value.

>>> print average([1, 2, 3])

2.0

"""

return sum(values, 0.0) / len(values)

import doctest

print doctest.testmod() # automatically validate the embedded tests, the case in doc string above can be cut and pasted from interpreter.

import unittest

class TestStatisticalFunctions(unittest.TestCase):

def test_average(self):

self.assertEqual(average([20, 30, 70]), 40.0)

self.assertEqual(round(average([1, 5, 7]), 1), 4.3)

self.assertRaises(ZeroDivisionError, average, [])

self.assertRaises(TypeError, average, 20, 30, 70)

# unittest.main() # Calling from the command line invokes all tests

# output formatting

print '\noutput formatting test'

import repr

print repr.repr(set('helloworldworldhelloyouareabigmanforallofus'))

import pprint

t = [[[['black', 'cyan'], 'white', ['green', 'red']], [['magenta', 'yellow'], 'blue']]]

pprint.pprint(t, width=30)

import textwrap

doc = """The wrap() method is just like fill() except that it returns

a list of strings instead of one big string with newlines to separate

the wrapped lines."""

print doc

print textwrap.fill(doc, width=40)

import locale

# locale.setlocale(locale.LC_ALL, 'English_United States.1252')

conv = locale.localeconv() # get a mapping of conventions

x = 1234567.8

print locale.format("%d", x, grouping=True)

# print locale.format("%s%.*f", (conv['currency_symbol'], conv['frac_digits'], x), grouping=True)

# templating

from string import Template

template = Template('${village}folk send $$10 to $cause.')

print template.substitute(village='Nottingham', cause='the ditch fund') # the parameter of template.substitue() support both "dict object" and the form of "(xxx = yyy, jjj = kkk)"

t = Template('Return the $item to $owner.')

d = dict(item='unladen swallow') # equals to d = {'item':'unladen swallow'}

# print t.substitute(d) # throw a exception saying: KeyError: 'owner'

print t.safe_substitute(d) # because of the line above, so we use safe_substitute instead of substitue. This will remain $owner in the string instead of a KeyError exception.

# use the new delimiter instead of $ above

class NewDelimiter(Template):

delimiter = '%'

print NewDelimiter('%jiawei is a good man.').substitute(jiawei='JIAWEI')

print

# multi-thread

import threading, zipfile

class AsyncZip(threading.Thread):

def __init__(self, infile, outfile):

threading.Thread.__init__(self)

self.infile = infile

self.outfile = outfile

def run(self):

f = zipfile.ZipFile(self.outfile, 'w', zipfile.ZIP_DEFLATED)

f.write(self.infile)

f.close()

print 'Finished background zip of: ', self.infile

background = AsyncZip('data', 'myarchive.zip')

background.start()

print 'The main program continues to run in foreground.'

background.join() # Wait for the background task to finish

print 'Main program waited until background was done.'

print

# loggin system

import logging

logging.debug('Debugging information')

logging.info('Informational message')

logging.warning('Warning:config file %s not found', 'server.conf')

logging.error('Error occurred')

logging.critical('Critical error -- shutting down')

# by default, debug and info above is suppressed, and all the logging message output is sent to standard error.

# add item to sorted list

import bisect

li = [1, 2, 3, 4, 5, 6]

bisect.insort(li, 0)

print li

print

# heappq make sure the smallest value put into the zero value.

from heapq import heapify, heappop, heappush

data = [1, 3, 5, 7, 9, 2, 4, 6, 8, 0]

print 'list before re-range: {0}'.format(data)

heapify(data) # rearrange the list into heap order

print 'list after re-range: {0}'.format(data)

heappush(data, -5) # add a new entry

print 'list after add new value -5: {0}'.format(data)

print 'fetch the three smallest entries: {0}'.format([heappop(data) for i in range(3)])

def fff():

return 'i'

print [fff() for i in range(3)]