Question

在Python中是否可以从单独的csv复制数据并将其放在另一个csv的特定列中？

我只想拍摄每个csv文件的第一列file1.csv file2.csv file3.csv

File1.csv Column A
File2.csv Column A
File3.csv Column A

并且只有一个output.csv，其中所有csv的column A数据都写入了自己的列

output.csv Column A (file1)
output.csv Column B (file2)
output.csv Column C (file3)

以下是我对过滤部分的看法，不知道如何为writer

执行此操作

 csvinputlist = ['file1.csv','file2.csv','file3.csv']


for csvinput in csvinputlist
    reader = csv.reader(open(r'{0}'.format(csvinput)), delimiter=',') 
    filtered = filter(lambda p:column A == p[0], reader)
    csv.writer(open(output.csv ???????

Answer 1

您可以使用pandas：

import pandas as pd
csvinputlist = ['file1.csv','file2.csv','file3.csv']
csvinput = csvinputlist
df = pd.DataFrame()
for i, csvinput in enumerate(csvinputlist):
    reader = pd.read_csv(csvinput) 
    df['A{}'.format(i+1)]=reader['A']

df.to_csv('constructed.csv')

其中＆＃39; A＆＃39;表示要读取的列的列标题。如果您的列没有标题，您可以按如下方式分配它们：

import pandas as pd
csvinputlist = ['file1.csv','file2.csv','file3.csv']
csvinput = csvinputlist
headers=['A', 'B', 'C'] # continue for as many column that are in the file
df = pd.DataFrame()
for i, csvinput in enumerate(csvinputlist):
    reader = pd.read_csv(csvinput, header=None, names=headers) 
    df['A{}'.format(i+1)]=reader['A']

df.to_csv('constructed.csv')

从csv文件写入特定列

1 个答案: