如何在读取CSV文件时将字符串值转换为整数值？

Question

打开CSV文件时，整数列将被转换为字符串值（'1'，'23'等）。通过循环将其转换回整数的最佳方式是什么？

import csv 

with open('C:/Python27/testweight.csv', 'rb') as f: 
    reader = csv.reader(f) 
    rows = [row for row in reader if row[1] > 's'] 

for row in rows: 
    print row 

CSV文件如下：

Account Value 
ABC  6 
DEF  3 
GHI  4 
JKL  7 

Answer 1

我想这你想要做什么：

import csv 

with open('C:/Python27/testweight.csv', 'rb') as f: 
    reader = csv.reader(f, delimiter='\t') 
    header = next(reader) 
    rows = [header] + [[row[0], int(row[1])] for row in reader] 

for row in rows: 
    print row 

输出：

['Account', 'Value'] 
['ABC', 6] 
['DEF', 3] 
['GHI', 4] 
['JKL', 7] 

Answer 2

如果CSV有头，我建议使用CSV.DictReader。随着代言人，你可以：

with open('C:/Python27/testweight.csv', 'rb') as f: 
    reader = csv.DictReader(f) 
    for row in reader: 
     integer = int(row['column that contains an int']) 

希望这有助于！

Answer 3

你可以只遍历所有的行如下：

import csv 

with open('C:/Python27/testweight.csv', 'rb') as f: 
    reader = csv.reader(f) 
    rows = [row for row in reader if row[1] > `s`] 

for index, cols in enumerate(rows[1:], 1): # Skip the header row 
    rows[index][1] = int(cols[1]) 

print rows 

这将显示：

[['Account', 'Value'], ['ABC', 6], ['DEF', 3], ['GHI', 4], ['JKL', 7]]