Have a look at regular expressions and grep!

Cheers, Sören

hey i did this , but there is some issue with the command , the first $ is not a part of regex as per perl . with this regex what i tried doing is that some $ before num and some $ after it . please tell what is the mistake

if ($array_A[$i] =~ /^$+[0-9]+$/)
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The /^$+ part makes no sense. If you you just want to test for the presence of digits then a simple /[0-9]/ will work splendidly.

" ... what i tried doing is that some $ before num and some $ after it "

Do you, by any chance, mean you tried to deal with data that included a "$" sign... such as:  abc12$ or  $98abc or  $$zyx5abc or something similar?

If so, you'll have to escape the "$" sign (with a preceding backslash, "\") in your regex.

perl -E "my $s='$abc123'; if ($s =~ /\$/ ) { say 'Found a dollar-sign';}

which outputs:

Found a dollar-sign

Otherwise, (slightly oversimplified), the regex engine uses the "$" sign is only to mark an EOL.

Updated by quoting a possibly mis-understood part of OP's latest question.


If you didn't program your executable by toggling in binary, it wasn't really programming!

Hi

Consider the following example under the Perl debugger:

  DB<1> @array=("aqw","asd8dsa","sd8sd","89","aws");

  DB<2>  @c = grep {/\d/} @array;

  DB<3> x @c
0  'asd8dsa'
1  'sd8sd'
2  89
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If the latter (which is the way I read "words") you'll need slightly more complex code:

#!/usr/bin/perl
use 5.016;
use strict;
use warnings;

# 1041443

my @array=("aqw","asd8dsa","sd8sd","89","aws", "17A", "bc24", );

for my $elem (@array) {
    if ( $elem =~ /\d/ ) {
        if ( $elem !~ /[\D]/ ) {
            say "No non-digits in *| $elem |*";
            next;
        }
        say $elem;
    } else {
        say "No numerals in *| $elem  |*";
    }
}
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OUTPUT:

No numerals in *| aqw  |*
asd8dsa
sd8sd
No non-digits in *| 89 |*
No numerals in *| aws  |*
17A
bc24
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What they’re all trying to say here is this:

1. A regular expression /[0-9]/ will do nicely:   you want an instance of a character in the inclusive range 0..9, anywhere in the string.
2. The function grep() is a handy shortcut that, given a list, will return another list containing those entries in the first list that match the regex ... in this case, “your answer.”