Programming Forums - Counting a single character in a string

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- - Counting a single character in a string (http://www.programmingforums.org/showthread.php?t=10693)

tbohon

Jul 12th, 2006 10:53 AM

Counting a single character in a string

I have a list of a directory and need to process the files depending on the number of underscore characters in the file name. For example, the files

filename_date.txt

and

file_name_date.txt

will be processed differently by the script.

I've tried

$count = ($data =~ tr/_/_/);

but it doesn't seem to work - I continue to get a zero (0) for $count.

Is there a flaw in my logic above? Is there a better way to do this?

Thanks in advance!

Tom

dr.p	Jul 13th, 2006 6:16 AM

You might post the other code that deals with the $count var. The example you posted looks correct.

Infinite Recursion

Jul 13th, 2006 9:46 AM

This works for me:

#!/usr/bin/perl



my $data = "this_is_a_test.txt";



$count = ($data =~ tr/_/_/);



print("Count is: $count\n");





[ir@grendel]# ./cchar.pl

Count is: 3

As an alternative, I wrote a small function also...



#!/usr/bin/perl



# Count letter frequency.

# Infinite Recursion - 13 JUL 2006



use strict;



my $base = "this_is_a_test.txt";

my $count = CountUnderscore($base);



print "Number of _ is: $count\n";





sub CountUnderscore ($base)

{

    my @find = ('_');

    my %freq = (); 



    foreach my $findc (@find) 

    {   

        my $count = 0;

        foreach my $basec (split(//, $base)) 

        {       

            if ($basec eq $findc)  

            {           

                ++$count;

            }           

        }       



        $freq{$findc} = $count; 

    }   



    return $freq{"_"};

}







[ir@grendel]# ./cfreq.pl

Number of _ is: 3

tbohon

Jul 13th, 2006 10:23 AM

Thanks to both of you. Turns out that the value I was moving to $data was wrong ... should have checked that before posting I guess ... just too many things happening at once and too many 'break/fixes' on my plate.

Appreciate it!

Best,

Tom

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