IndexError：使用csv列出索引超出范围

Question

I have CSV file that contains multiple columns when I run this code in the first column, will run fine, but when I run it in another column, will display this error
IndexError: list index out of range

array_of_ids = []
with open('reactions/by_ids.csv','r',newline='') as f:
  reader = csv.reader(f)

  for row in reader:
    array_of_ids.append(row[2])

so, row[0] works, row[2] does not work!!

Answer 1

You should take a look at your CSV file in a file editor and ensure that each line contains at least 3 entries. A common problem is when your CSV file contains a blank link eg the last line.

You could always add if len(row) == 3: before doing your append, this would then have the effect of skipping over any lines that are not correctly formated, for example:

import csv

array_of_ids = []

with open('reactions/by_ids.csv', 'r', newline='') as f:
    reader = csv.reader(f)

    for row in reader:
        if len(row) == 3:
            array_of_ids.append(row[2])