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[Python] 将csv文件中单个列的多个value拆分成多个列的单个value

showerlee 2015-03-23 16:59 LAN, PYTHON 阅读 (2,005) 抢沙发

    很久没有更新博客了,最近handle了一个项目需要处理大量csv文件,需求是将csv文件中某单个列的多个values(该多个vaules以回车分隔)拆分成多个相同列的单个value,由于python在处理脚本先天比shell更有优势,这里把自己的最近学到python知识加以应用,编写了一个脚本,供大家参考.

#!/usr/bin/env python

import csv
import sys

# Define the duality list
Csv_content_edited = []

# Define the file that needs to be handled.
try:
	file_name = sys.argv[1]
	new_file_name = file_name.split('.')[0] + '_new.' + file_name.split('.')[1]
except IndexError:
	pass

# Define the collumns that need to be dealt with.
Field = ['Affects Version/s','Fix Version/s','Component/s']

"""
 Search the index numbers of each components of "Field" list in the first row of csv file,
 return the dic["field value":"the index of first_row"] 
"""
def search_field_index(field, first_row):
	fields_dic = {}
	for x in first_row:
		if x in field:
			fields_dic[x] = first_row.index(x)
	return fields_dic

'''
  Find the maximum value number of each "Field" components in "Csv_content_edited" list,
  then insert the actual number of the columns after each "Field" columns.
'''
def insert_max_col(field_index,Field_val):
	# Define the list stored maximum number of the value of the field
	index_len = []
	# Define the list stored the value of the field
	index_val = []
	# Recursive the row from 2 ~ max of the csv field
	for r in range(1,len(Csv_content_edited)):
		# Deal with special string
		c = repr(Csv_content_edited[r][field_index]).split("\\r")
		index_len.append(len(c))
		index_val.append(c)
	# The maximum component of the "index_len" list
	max_index_len = max(index_len)

	# Clear " " and "'" string which are in the head or tail of each "index_val" components.
	for iv in range(0,len(index_val)):
		for _iv in range(0,len(index_val[iv])):
			index_val[iv][_iv] = index_val[iv][_iv].strip(' \'')

	# insert null value collumn after the field from "Field" list to the "Csv_content_edited" list
	for i in range(0,len(Csv_content_edited)):
		for m in range(0,max_index_len - 1):
			Csv_content_edited[i].insert(field_index + m + 1,'')

	# Update the first row of "Csv_content_edited" list to the field components from "Field" list
	for i1 in range(field_index,field_index + max_index_len):
		Csv_content_edited[0][i1] = Field_val

	# Update the rest rows of "Csv_content_edited" list to the field components from "index_val" list
	for i in range(1,len(Csv_content_edited)):
		for i2 in range(field_index,field_index + max_index_len):
			try:
				Csv_content_edited[i][i2] = index_val[i-1][i2 - field_index]
			except IndexError as s:
				pass

	# return Csv_content_edited[3],index_val,max_index_len
	# return len(Csv_content_edited),len(index_val)
	# print max_index_len
	# print index_val[2][0]
	# return len(index_val[2])


# Read and deal with the csv file. 
def readContent(file_name):
	# Read the csv file,then put it into list.
	with open(file_name, 'r') as csvfile:
		csv_reader = csv.reader(csvfile, delimiter=',')
		for row in csv_reader:			 
			if row[0] == 'Key':	
				first_row = []		
				first_row = row
				# insert first row of csv to the list
				Csv_content_edited.append(first_row)
			else:
				# insert rest row of csv to the list
				Csv_content_edited.append(row)
		else:
			# Obtain all current "Field" index in "Csv_content_edited" list
			fields_index = search_field_index(Field,first_row)
			# Obtain the index of "Affects_Version" in in "Csv_content_edited" list
			Affects_Version_index = fields_index[Field[0]]
			# insert the matching value
			insert_max_col(Affects_Version_index,Field[0])

			# Obtain all current "Field" index in "Csv_content_edited" list
			first_row_updated = Csv_content_edited[0]
			fields_index = search_field_index(Field,first_row_updated)		
			# Obtain the index of "Affects_Version" in in "Csv_content_edited" list
			Fix_Version_index = fields_index[Field[1]]
			# insert the matching value
			insert_max_col(Fix_Version_index,Field[1])

			# Obtain all current "Field" index in "Csv_content_edited" list
			first_row_updated = Csv_content_edited[0]
			fields_index = search_field_index(Field,first_row_updated)
			# Obtain the index of "Affects_Version" in in "Csv_content_edited" list
			Fix_Version_index = fields_index[Field[2]]
			# insert the matching value
			insert_max_col(Fix_Version_index,Field[2])
	# Obtain the final edited list.
	return Csv_content_edited

# Write the csv file. 
def writeContent():
	with open(new_file_name,'wb') as csvfile:
		csv_writer = csv.writer(csvfile)
		csv_writer.writerows(readContent(file_name))

# Execute the finnal function.	
if __name__ == '__main__':
	try:
		writeContent()
	except (IOError,NameError,IndexError):
		print "Please type the correct file name. e.g: '" + sys.argv[0] + " testfile.csv'"
	else:
		print 'The result file is: %s' %new_file_name



处理前的效果

QQ20150323-1

处理后的效果

QQ20150323-2

如有雷同,纯属扯淡...

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