数据挖掘：python数据清洗cvs里面带中文字符

　　数据清洗，使用python数据清洗cvs里面带中文字符，意图是用字典对应中文字符，即key值是中文字符，value值是index，自增即可；利用字典数据结构没有重复key值的特性，把中文字符映射到了数值index。

　　python代码如下：（data数据时csv格式）

import csv

dict2 = {}      #C
dict4 = {}      #E
dict25 = {}     #z
dict26 = {}     #AA
dict27 = {}     #AB
dict37 = {}     #AL
dict38 = {}     #AM
dict40 = {}     #AO
dict41 = {}     #AP
dict42 = {}     #AQ
dict45 = {}     #AT
dict49 = {}     #AX
index = 0
flag = False

#        print(row[2],dict[row[2]])

with open("E:/test/real/test.csv", 'w+', newline='') as csv_file_write:
        writer = csv.writer(csv_file_write)
        with open('E:/test/real/b.csv', 'r', newline='') as csv_file_read:
            reader = csv.reader(csv_file_read)
            for row in reader:
                if(flag):
                    if row[2] not in dict2.keys():
                        dict2[row[2]] = index
                    if row[4] not in dict4.keys():
                        dict4[row[4]] = index
                    if row[25] not in dict25.keys():
                        dict25[row[25]] = index
                    if row[26] not in dict26.keys():
                        dict26[row[26]] = index
                    if row[27] not in dict27.keys():
                        dict27[row[27]] = index
                    if row[37] not in dict37.keys():
                        dict37[row[37]] = index
                    if row[38] not in dict38.keys():
                        dict38[row[38]] = index
                    if row[40] not in dict40.keys():
                        dict40[row[40]] = index
                    if row[41] not in dict41.keys():
                        dict41[row[41]] = index
                    if row[42] not in dict42.keys():
                        dict42[row[42]] = index
                    if row[45] not in dict45.keys():
                        dict45[row[45]] = index
                    if row[49] not in dict49.keys():
                        dict49[row[49]] = index
                    row[2] = dict2[row[2]]
                    row[4] = dict4[row[4]]
                    row[25] = dict25[row[25]]
                    row[26] = dict26[row[26]]
                    row[27] = dict27[row[27]]
                    row[37] = dict37[row[37]]
                    row[38] = dict38[row[38]]
                    row[40] = dict40[row[40]]
                    row[41] = dict41[row[41]]
                    row[42] = dict42[row[42]]
                    row[45] = dict45[row[45]]
                    row[49] = dict49[row[49]]
                    index = index + 1
                writer.writerow(row)
                flag = True
        csv_file_read.close()
csv_file_write.close()

print('done!')

　　上例是真实的数据处理，有两百列属性，三万条数据的原始数据。其中包括中文字符，及缺失值，需要一步步清洗。

　　备注：发生异常permission denied异常；

　　解决方案：　是因为正在打开着csv文件，所以python没有权限以w的方式打开文件。关闭该文件即可；