Python-module

repeat

In [1]: from itertools import repeat
In [2]: x = list(repeat(0,times=10))
In [3]: x
Out[3]: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

OrderedDict

按照书写顺序输出字典中的元素

from collections import OrderedDict
orderdict1 = OrderedDict()
content = ((key1,val1), (key2,val2), (key3,val3))
orderdict2 = OrderedDict(content)

filter

Help on built-in function filter in module __builtin__:

filter(...)

filter(function or None, sequence) -> list, tuple, or string

Return those items of sequence for which function(item) is true. If

function is None, return the items that are true. If sequence is a tuple

or string, return the same type, else return a list.

(END)

CSV

read

import csv
csvfile = file(inputfile, 'rb')
csvreader = csv.reader(csvfile)
for line in csvreader:
    ISBN.append(line[0])
csvfile.close()

write

import csv
#ASIN and isbns are list with the same of length.
Asinfile = file(outputfile,'wb')
Asinwriter = csv.writer(Asinfile)
rowdata = []
for i in xrange(len(ASIN)):
    data = [isbns[i], ASIN[i]]
rowdata.append(data)
Asinwriter.writerows(rowdata)
Asinfile.close()

codecs & unicodedata

文件字符编码问题

import codecs
file = codecs.open("lol", "w", "utf-8")
file.write(u'\ufeff')
file.close()

import unicodedata
isbn = unicodedata.normalize('NFKD', isbn).encode('utf-8','ignore')

sys

import sys
sys.setrecursionlimit(150) #设置递归深度

argparse

import argparse
'''
input : argv[1] or image path
output: book spine segment images which store in './Example/Dst'
Usage :    $ python.py --image=
eg:
$ python main.py --image='./Example/Src/002.jpg'
'''

# Load image for command line operator
ap = argparse.ArgumentParser()
ap.add_argument("-i", "--image", required = True, help = "Path to the image") args = vars(ap.parse_args())
InputImg = cv2.imread(args["image"])  
# "./Example/Src/002.jpg"

OptionParser

from optparse import OptionParser

parser = OptionParser()

parser.add_option("-i", "--input",  action="store", dest="DateTimeFile", help="Load datetime file.")

parser.add_option("-o", "--output1", action="store", dest="bookbid",  help="Write changing of book id.")

parser.add_option("-f", "--output2", action="store", dest="userid",      help="Write changing of user id.")

(options,args) = parser.parse_args()

DateTimeFile  = options.DateTimeFile
bookbid       = options.bookbid
userid        = options.userid

……