merging two .txt files by alternating x lines from file 1 and y lines from file2

Shell Programming and Scripting
1

Hi everyone,

I have two files (A and B) and want to combine them to one by always taking 10 rows from file A and subsequently 6 lines from file B. This process shall be repeated 40 times (file A = 400 lines; file B = 240 lines).

Does anybody have an idea how to do that using perl, awk or sed?

Thank you so much in advance!
Iris

------------------------------------------------------------------------------
File A
------------------------------------------------------------------------------

0000 0    BIROB    18    brb    PSI    2    99
0001 17    ROBER    9    rbr    PSI    2    99
0002 5   TASOT    16    tst    PSI    2    99
0003 78    KASEK    6    ksk    PSI    2    99
...

-------------------------------------------------------------------------------
File B
-------------------------------------------------------------------------------

0000 N    NNNNN    N    N    CCCCC    NNN    2
0001 P    PPPPP    P    P    CCCCC    PPP    1
0002 P    PPPPP    P    P    CCCCC    PPP    1
0003 P    PPPPP    P    P    CCCCC    PPP    1
0004 N    NNNNN    N    N    CCCCC    NNN    2
2

Could this help you? (Code not tested)

#!/bin/sh
i=0
j=6
k=0
while read line1
do
    echo $line1
    i=$i+1
    if [ $i -eq 10 ]
    then
        awk -v start=$k -v end=$j  'NR > start && NR <= end' file2
        k=$j
        j=$j+6
        i=0
    fi
done < file1
3

Thanks!
Unfortunately, it doesn't read or print the lines from file2 so that it just takes all lines from file1 and prints those.

Any idea why it doesn't do the if loop?

4

Try this,

#!/bin/sh
i=0;j=6;k=0
while read line1
do
    echo $line1
    i=$(($i+1))
    if [ $i -eq 10 ]
    then
        awk -v start=$k -v end=$j  'NR > start && NR <= end' file2
        k=$j;j=$(($j+6));i=0
    fi
done < file1
1 Like
5

Thank you so much! It now works perfectly!

6

A Perl:

#!/usr/bin/perl
use strict;

my $fileA=shift;
my $fileB=shift;
my $fileR=shift;

open (FA,"<",$fileA ) || die "Can't open $fileA\n";
my @txtA=<FA>;
close(FA);

open (FB,"<",$fileB ) || die "Can't open $fileB\n";
my @txtB=<FB>;
close(FB);

open (FR,">",$fileR ) || die "Can't open $fileR\n";

my ($contA,$a,$contB,$b)=0;

for my $i ( 1 .. 40 ) {
   for $a ( 1 .. 10 ) {
      $a+=$contA;
      print FR $txtA[$a];
      }
   $contA+=10;
   for $b ( 1 .. 6 ) {
      $b+=$contB;
      print FR $txtB[$b];
      }
   $contB+=6;
   }    

close(FR);
    
exit;

Usage:

script.pl filea fileb result
1 Like
7

By shell script:

i=1;j=1;k=10;l=6
line=`cat file1 |wc -l`

while (true)
do
    m=`expr $i + $k - 1`
    n=`expr $j + $l - 1`
    sed -n "${i},${m}p" file1
    sed -n "${j},${n}p" file2
    i=`expr $i + $k`
    j=`expr $j + $l`
    if [ $i -gt $line ]; then
      exit
    fi
done

One-line awk (speed faster, because file1 and file2 are only read by one time.)

awk 'NR%10{print;next} {print;for (i=1;i<=6;i++) {getline < "file2";print} }' file1
1 Like