Counting Characters

[Anonymous Monk]

Hi, this should be simple but...I need to count the number of characters set in the variable ($summary). My $summary variable takes the first 500 characters from another variable $text. Sometimes $text might be less than 500 characters so I need to count the number of characters that actually end up in the variable $summary. This is how I get the summary variable...

$summary = substr($text, 0, 500);

Thanks.

[ikegami]

Use length. Specifically, use length($summary).

In context:

$text = '.'x400;
$summary = substr($text, 0, 500);
print(length($summary), "\n");    # 400

$text = '.'x500;
$summary = substr($text, 0, 500);
print(length($summary), "\n");    # 500

$text = '.'x600;
$summary = substr($text, 0, 500);
print(length($summary), "\n");    # 500

[xdg]

As an addendum -- in case it's not clear for the OP or others -- this works because substr used in the way described takes up to as many characters specified (e.g. 500 in this case). If used on a string shorter than the maximum length, there is no padding added at the end. Thus length works on the summary exactly as one would expect.

[PodMaster]

Always search first, you'll save yourself time.
A simple search for count characters returns:
• How do I count characters
• Counting number of characters in a string
• Counting Characters
And length is always the first answer.

[CountZero]

print scalar split '', $summary; or if you really want to count the number of characters: map {$count++} split '', $summary; print $count;

Of course none of these is efficient, but if you really do not want to use the built-in length function, ...

[antirice]

Don't forget about print $summary =~ y///c;.

[GrandFather]

or counting nibbles and dividing by two (bit fraught for multi-byte characters though):

use strict;
use warnings;

my $text = '.'x400;
my $summary = substr($text, 0, 500);
print length(unpack 'H*', $summary) / 2, "\n";

Prints:

400