Hello PerlMonks,
I would like to open a file and read it line by line. I've created a subroutine to do this which takes the file path as an input variable. A file handle is then opened for this file.

As the file is read, I would like to count the number of occurances of the word 'Algorithm' at the beginning of a line. If it occurs, I want to increment a counter.

If the words 'Experiment Name' occurs at the beginning of a line, the if loop exits and the subroutine returns the value of the counter. 

sub getExpNumber {
 my ($filePath) = @_;
 my ($n) = 0;
 
 open (INPUT, $filePath) or die "Can't open $filePath: $!\n";
 while (<INPUT>) {
  chomp;
  if (<INPUT> =~ /^Experiment Name/) {
   print "There are $n experiments in $filePath: $!\n";
  } elsif (<INPUT> =~ /^Algorithm/) {
   $n++;
   next;
  } else {
   next;
  }
 close(INPUT) or die "Can't close $filePath.$!\n";
 }
return $n; 
}

[download]
My problem is that it only counts the first occurance of 'Algorithm' - the rest are ignored. Does anyone have a suggestion on what to change?

I am running with use strict and I am using the -w on the #! line

Thanks

MadraghRua
yet another biologist hacking perl....

In reply to Counting occurances of a pattern in a file by MadraghRua

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