Question

我有一个包含大量列的csv文件，而某些列的行数比其他列多。我试图读取某些列并将这些列提取到不同的csv文件。但是，我继续使列表索引超出范围，因为我正在读取的列比csv文件中的其他列短。

import csv
import os
import os.path

'Open csv directory to extract data from'
path = 'S://Raw Data/VehicleData/'               

'Get file names and print number of files in the directory'
files = [f for f in os.listdir(path)]
print(files)
print(len(files))

'Start loop to scan through files in directory'
for j in range(len(files)):

'determine name of file and the output name of the file'
name = files[j]
print(name)

'path to file to open'
fpath = os.path.join(path, files[j])

    if files[j].endswith(".csv"):
        nameout = 'VehicleN3STPData' + '.csv'
        with open (fpath, 'r', newline='') as csvfile:
            testcsv = csv.reader(csvfile,delimiter=',')
            with open (nameout,'a+',newline='') as outfile:
                writer = csv.writer(outfile)
                for row in testcsv:
                    my_row = []
                    my_row.append(row[59])
                    my_row.append(row[111])
                    my_row.append(row[120])
                    print(my_row)
                    writer.writerow(my_row)
                outfile.close()    
        csvfile.close()

Answer 1

你需要一个条件陈述来检查长度，或者你需要一个尝试＆amp;除了条款取决于您的预期行为。

以下是使用条件语句的示例，如果它们不存在，则将列值保留为空白。

而不是：

my_row.append(row[59]) 
my_row.append(row[111]) 
my_row.append(row[120])

执行：

for col_num in [59, 111, 120]:
    my_row.append(row[col_num] if len(row) > col_num else '')

Answer 2

感谢您的帮助，这里是最终的代码，使用islice删除标头，使用条件语句，然后删除空白行if if（my_row）thanks !!

    if files[j].endswith(".csv"):
    nameout = 'VehicleN3STPData' + '.csv'
    with open (fpath, 'r', newline='') as csvfile:
        testcsv = csv.reader(csvfile,delimiter=',')
        with open (nameout,'a+',newline='') as outfile:
            writer = csv.writer(outfile)
            for row in islice(testcsv,3,None):
                    my_row = []
                    for col_num in [59,111,120]:
                        my_row.append(row[col_num] if len(row) > col_num else '')
                    if any(my_row):
                        writer.writerow(my_row)
            outfile.close()    
    csvfile.close()enter code here

读取CSV文件会导致列表索引超出范围

2 个答案: