how to print nth column in a file using awk

Question

How to print nth column in a file using awk?To print the second column of file, I try:

#!/bin/bash   
awk '{print $2}' file

But if n is a variable, how to print nth column of file using awk?

#!/bin/bash   
n=2

This is a dupe, you can see lots of similar questions on this topic of using shell variables in `Awk`. The title could suggest awk script, but it is all the same, using shell variables in a script (or) command — Inian, Oct 30 '17 at 09:12

score 4 · Accepted Answer · answered Oct 30 '17 at 09:07

4

n=2
awk -v var="$n" '{print $var}' file

answered Oct 30 '17 at 09:07

tso

score 2 · Answer 2 · answered Oct 30 '17 at 09:10

Give a try this, notice the -v option:

#!/bin/bash

n=3

awk -v x=${n} '{print $x}' file

From the man page:

The option -v followed by var=value is an assignment to be done before 
prog is executed; any number of -v options may be present.

For more examples, you could check Using Shell Variables in Programs

2 Answers2