CSV(Comma-Separator Values)逗号分割值,由于是纯文本文件,任何编辑器都可以打开。下面用csv和pandas两种方式进行csv文件操作
原始csv文件内容
Supplier Name,Invoice Number,Part Number,Cost,Purchase Date Supplier X,001-1001,2341,$500.00 ,1/20/14 Supplier X,001-1001,2341,$500.00 ,1/20/14 Supplier X,001-1001,5467,$750.00 ,1/20/14 Supplier X,001-1001,5467,$750.00 ,1/20/14 Supplier Y,50-9501,7009,$250.00 ,1/30/14 Supplier Y,50-9501,7009,$250.00 ,1/30/14 Supplier Y,50-9505,6650,$125.00 ,2002/3/14 Supplier Y,50-9505,6650,$125.00 ,2002/3/14 Supplier Z,920-4803,3321,$615.00 ,2002/3/14 Supplier Z,920-4804,3321,$615.00 ,2002/10/14 Supplier Z,920-4805,3321,"$6,015.00 ",2/17/14 Supplier Z,920-4806,3321,"$1,006,015.00 ",2/24/14
1. csv包操作csv文件
#coding=utf-8 import sys import csv import re read_file = sys.argv[1] write_file = sys.argv[2] with open(read_file, "r") as readfile: with open(write_file, "w") as writefile: reader = csv.reader(readfile, delimiter=",") writer = csv.writer(writefile, delimiter=",") header = next(reader) writer.writerow(header) for rowlist in reader: #通过正则表达是进行行匹配 if re.match(r"^001-*.", str(rowlist[1])): print (rowlist) writer.writerow(rowlist)
>>> D:\Pystu>python parsecsvfile.py supplier_data.csv ceshi.csv
>>> Supplier Name,Invoice Number,Part Number,Cost,Purchase Date
>>> Supplier X,001-1001,2341,$500.00 ,1/20/14
>>> Supplier X,001-1001,2341,$500.00 ,1/20/14
>>> Supplier X,001-1001,5467,$750.00 ,1/20/14
>>> Supplier X,001-1001,5467,$750.00 ,1/20/14
2. pandas包操作csv文件
#coding=utf-8 ‘‘‘ 运用pandas包解析csv文件‘‘‘ import pandas from pandas import Series,DataFrame import sys file_path = sys.argv[1] write_path = sys.argv[2] data_frame = pandas.read_csv(file_path) #print (data_frame) #注意str的使用 data_frame["Cost"] = data_frame["Cost"].str.replace(",", "").str.strip("$").astype(float) #print (data_frame) newa = data_frame.loc[data_frame["Cost"] > 600, :] #print (newa) newa.to_csv(write_path, index = False)
>>> D:\Pystu>python parse_csv_file_by_pandas.py supplier_data.csv ceshi.csv
>>> Supplier Name,Invoice Number,Part Number,Cost,Purchase Date
>>> Supplier X,001-1001,5467,750.0,1/20/14
>>> Supplier X,001-1001,5467,750.0,1/20/14
>>> Supplier Z,920-4803,3321,615.0,2002/3/14
>>> Supplier Z,920-4804,3321,615.0,2002/10/14
>>> Supplier Z,920-4805,3321,6015.0,2/17/14
>>> Supplier Z,920-4806,3321,1006015.0,2/24/14