in reply to Re: handling tab delimited files
in thread handling tab delimited files

open FILE, "96well2.txt" or die $!;
 while (<FILE>){
 chomp $_;
  @values = split('\t', $_);
  $val = @values;
  print $val;
 }
 close (FILE);

[download]
This is what printing $val gives 111111111111

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Re^3: handling tab delimited files
by almut (Canon) on May 05, 2010 at 17:21 UTC

    As $val = @values assigns the number of elements in the array to $val, your output confirms my suspicion, i.e. that the lines aren't tab separated, so you get only one value in @values (the entire line) from the split.

    Try splitting on whitespace: 

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

print " Enter the dilution factor. \n";
chomp (my $df = <STDIN>);
open FILE, "45well.txt" or die $!;
while (<FILE>){
    chomp;
    my @values = split ' ';
    foreach my $val (@values){
        my $DNA_conc = $val * $df * 50 ;
        print "$DNA_conc\n";
    }
}
close (FILE);

    [download]
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      The code has started to work finally.. but the problem is it is giving the output in one column and splitting all the values.

      so for the line :

      0.250 0.413 0.432 0.345 0.786 1.001 0.987

      the output is : 

      125
206.5
216
172.5
393

      [download]

      and so on

      how should i put it back together? This is the code i used : 

      use warnings;
print " Enter the dilution factor. \n";
chomp ($df = <STDIN>);
open FILE, "96well.txt" or die $!;
while (<FILE>){
 chomp $_;
  @values = split('\t', $_);

foreach $val (@values){
$DNA_conc = $val * $df * 50 ;
print $DNA_conc;
print"\n";
}
}
 close (FILE);

      [download]
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[d/l]
[select]
        how should i put it back together?

        You could write 

            foreach my $val (@values){
        $val *= $df * 50 ;
    }
    print join("\t", @values), "\n";

        [download]

        This would modify the values in-place in the array (because $val is an alias for the respective elements in the array), so you can simply join them with a tab after the for loop.

        Or shorter, with map: 

            print join("\t", map { $_ * $df * 50 } @values), "\n";

        [download]

        or maybe even 

        ...
while (<FILE>){
    print join("\t", map { $_ * $df * 50 } split /\t/), "\n";
}

        [download]
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[select]
        yeeeeeeeeeeeee my code is working... I know i m just posting on my own... but this is what is did!! 
         print " Enter the number. \n";
 chomp ($df = <STDIN>);
 open FILE, "45well.txt" or die $!;
 while (<FILE>){
 chomp $_;
  @values = split('\t', $_);
   foreach $val (@values){
   $DNA_conc = $val * $df * 50 ;
 print $DNA_conc;
 print"\t";
 }
 }
  print "\n";
 close (FILE);

        [download]
        any ideas on how to Print the converted values out into another tab-delimited file of equal dimensions (12 x 8), with a header in the file to tell what was done. thank you so much toolic and almut for your help
[reply]
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