Awk print all columns and the modified column

June 28, 2022

Say I have a text file test

chr1    16597656        16597657        Chr1:16924151
chr1    149015385       149015386       Chr1:144869084
chr1    148989775       148989776       Chr1:144894697

I need to modify the fourth column and get the result like this

chr1    16597656        16597657     Chr1:16924151   Chr1:16924150-16924151
chr1    149015385       149015386    Chr1:144869084  Chr1:144869083-144869084
chr1    148989775       148989776    Chr1:144894697  Chr1:144894696-144894697

I tried awk -F '[:]' '{print $1":"$2-1"-"$2}' test which doesn’t print the fourth column in my result. What am I missing here?

>Solution :

You might print the whole line and use split on the 4th column to assemble the values for the 5th column.

awk '
{
  split($4,a,":")
  print $0 OFS a[1] ":" a[2]-1 "-" a[2]
}
' file

Output

chr1    16597656        16597657        Chr1:16924151 Chr1:16924150-16924151
chr1    149015385       149015386       Chr1:144869084 Chr1:144869083-144869084
chr1    148989775       148989776       Chr1:144894697 Chr1:144894696-144894697

If you field separator is a tab:

awk '
BEGIN {FS=OFS="\t"}
{
  split($4,a,":")
  print $0 OFS a[1] ":" a[2]-1 "-" a[2]
}
' file

Output

chr1    16597656        16597657        Chr1:16924151   Chr1:16924150-16924151
chr1    149015385       149015386       Chr1:144869084  Chr1:144869083-144869084
chr1    148989775       148989776       Chr1:144894697  Chr1:144894696-144894697