Shell Programming and Scripting

chr2L	552	0.85
chr2R	135	1.06
chr3L	820	2.89
chr3R	581	3.93
chr4	585	0.94
chrX	605	1.93

chr2L	552	0.22
chr2R	135	0.27
chr3L	820	0.76
chr3R	581	1.00
chr4	585	0.94
chrX	605	0.50

y=`sort -k3,3nr filename | awk 'NR == 1 { print $3}'`
awk '{$3 = $3 / '$y';printf("%s\t%d\t%0.2f\n", $1, $2, $3);}' filename

chr2L   552     0.22
chr2R   135     0.27
chr3L   820     0.74
chr3R   581     1.00
chr4    585     0.24
chrX    605     0.49

#!/usr/bin/perl
use strict;
use warnings;

open(FH,"inputfilename");
my @LINE;
my @val;
my $counter=0;
open OUT, ">./BG3_H3K27ac_Ave_Rto.to2006_Norm.sgr";
while(my $line=<FH>){
   my @array=split("\t",$line);
   push(@LINE, $line);
   push(@val,$array[2]);
   $counter++;
   }
   close(FH);

   my @valst=sort { $a <=> $b } @val;
   my $idx=$valst[$counter-1];

   foreach my $line(@LINE){
   my @array=split("\t",$line);
   print OUT $array[0],"\t",$array[1],"\t",$array[2]/$idx,"\n";
}

awk '
{a[NR]=$1; b[NR]=$2; c[NR]=$3; $3 > mx ? mx=$3 : 0}
END { for (i=1; i<=NR; i++) printf ("%-6s%6d%7.2f\n", a[i], b[i], c[i]/mx ); }
' infile