如何在python中从txt中选择不同的列

Question

I want to print out my first column with other columns(as tab seperated) respectively. For example Col1+Col2 for first print, Col1+Col3 for second Col1+Col4 so on. However I printed out just Col1+Col2 with my code below. Why for loop is not progressing?

import csv
with open('/Users/elf/Desktop/TEST_DATA/text_haplo.txt', 'r', encoding="utf-8", errors="ignore") as text_haplo:
    next(text_haplo)
    for i in range(1, 5):
        for line in text_haplo:
            line = line.split('\t')
            print(line[0], line[i])

The input is:

A    1    2    3
B    10   20   30
C    100  200  300

And I want the output sth like:

A 1
B 10
C 100

A 2
B 20
C 200

A 3
B 30
C 300

Answer 1

Updated version:

for i in range(1, 4):
    with open('test.csv') as f:
        for line in f:
            line = line.rstrip().split('\t')
            print(line[0], line[i])
        print()

However, it's not a good practice to read the file again and again. It is acceptable only if your target machine lacks the RAM or the file is extremely big. Otherwise it's better to read it once to memory and then output it in desired order:

data = []
with open('test.csv') as f:
    for line in f: data.append(line.rstrip().split('\t'))

for i in range(1, 4):
    for columns in data:
        print(columns[0], columns[i])
    print()