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in reply to Re^8: incrementing already existing file
in thread incrementing already existing file

Show us the code you tried. For that desired output, the modifications to the code I posted are not that complicated, especially with the suggestions that I already made. What I already said about collecting values from MYFILE will still work. Here are some additional hints to create the output you want:

That's all there is to it. Give it another go and post back with your code if you need more help.

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Re^10: incrementing already existing file
by wanttoprogram (Novice) on Mar 03, 2011 at 06:16 UTC
    #!/usr/bin/env perl use strict; use warnings; my $file1 = "2hgs_d00_internal_nrg_e.dat"; my $file2 = "2HGS_bio_conv-min_p.pdb"; open( MYFILE, '<', $file1 ) or die "cannot open $file1: $!"; open( NEWF, '<', $file2 ) or die "cannot open $file2: $!"; my (@a_vals, @b_vals); while ( <MYFILE> ) { chomp; my( $label, $index, $value ) = ( split /\s+/ )[3, 5, -1]; $a_vals[ $index ] = $value; $b_vals[ $index ] = $value; } close MYFILE; while ( <NEWF> ) { chomp; my @fields = ( split /\s+/ ); my $index = $fields[4]; my $label = $fields[-1]; if ($label eq "A"){ $fields[-2] = $a_vals[ $index ] } if ($label eq "B"){ $fields[-2] = $b_vals[ $index ] } my $output = join "\t", @fields; print "$output\n"; } close NEWF;
    I am still getting values from B from MYFILE
      In this section of your code:
      while ( <MYFILE> ) { chomp; my( $label, $index, $value ) = ( split /\s+/ )[3, 5, -1]; $a_vals[ $index ] = $value; $b_vals[ $index ] = $value; }
      You need to check the value of $index to get the values for type 'A' into @a_vals, similarly for the 'B' values. The way you have it, you only get 'B' values because they are the last ones in MYFILE, and you are putting the same things into both @a_vals and @b_vals. Since the 'B' values come in last, they overwrite the corresponding 'A' values in @a_vals. You can use the same kind of if/elsif/else logic as in your other loop to fix this(but see comments below on ways to improve that).

      Now for this part of the loop over NEWF:

      if ($label eq "A"){ $fields[-2] = $a_vals[ $index ] } if ($label eq "B"){ $fields[-2] = $b_vals[ $index ]

      You should use if / elsif / else here:

      if ($label eq "A") { $fields[-2] = $a_vals[ $index ] } elsif ($label eq "B") { $fields[-2] = $b_vals[ $index ] } else { print "OOPS! bad label\n"; # complain if something is fishy }

      You're getting there.

        Perfect. It worked. Thank you for your clean answers and time.