How can I check if a value is numeric, alphabetical or alphanumeric in Perl?

I have array which values are user input like:

aa df rrr5 4323 54 hjy 10 gj @fgf %d

Now I want to check each value in array to see whether it's numeric, alphabetic (a-zA-Z), or alphanumeric and save them in other respective arrays.

I have done:

my @num;
my @char;
my @alphanum;

my $str =<>;
  my @temp = split(" ",$str);
        foreach (@temp)
           {
                print "input : $_ \n";
                if ($_ =~/^(\d+\.?\d*|\.\d+)$/)
                    {
                        push(@num,$_);
                    }
           }

This works. Similarly I want to check for alphabet, and alphanumeric va开发者_如何学Golues

Alphanumeric example are: fr43 6t$ $eed5 *jh

Perl supports POSIX character classes, so you can actually do this:

$string =~ /^[[:alpha:]]+$/;
$string =~ /^[[:alnum:]]+$/;

Numbers are less well defined, but Scalar::Util's looks_like_number function may do what you want it to do.

The answer you accepted doesn't produce the results which you claim to want in your question. Specifically, the POSIX character class [:alphanum:] will not match punctuation characters meaning that 6t$ $eed5 *jh will not be matched. In order to match punctuation characters you need to add [:punct:] to the char class. See the Regex cheat sheet.

So for example if you have the file tokens.txt which contains:

aa df rrr5 4323 54 hjy 10 gj @fgf %d fr43 6t$ $eed5 *jh

And you run this perl script:

#!/usr/bin/perl -w
use warnings;
use diagnostics;
use strict;
use Scalar::Util qw( looks_like_number );


my $str =<>;
my @temp = split(" ",$str);

my @num = grep { looks_like_number($_) } @temp;
my @char = grep /^[[:alpha:]]+$/, @temp;
my @alphanum = grep /^[[:alnum:][:punct:]]+$/, @temp;

print "Numbers: " . join(' ', @num) . "\n";
print "Alpha: " . join(' ', @char) . "\n";
print "Alphanum: " . join(' ', @alphanum) . "\n";

like this:

cat tokens.txt | ./tokenize.pl

You get the output:

Numbers: 4323 54 10
Alpha: aa df hjy gj
Alphanum: aa df rrr5 4323 54 hjy 10 gj @fgf %d fr43 6t$ $eed5 *jh

However, it seems by your question that you don't want to match all punctuation characters such as @ and %, but instead only certain ones such as $ and *.

If that's the case then you just change the Alphanum match to:

my @alphanum = grep /^[[:alnum:]\$\*]+$/, @temp;

Which will then give you the desired output of

Numbers: 4323 54 10
Alpha: aa df hjy gj
Alphanum: aa df rrr5 4323 54 hjy 10 gj fr43 6t$ $eed5 *jh

For separating the input into arrays something like this would work and allow easy additions or changes to your matches.

my $input = 'aa df rrr5 4323 54 hjy 10 gj @fgf %d';
my %tests = ( 
    num   => '\d+',
    alpha => '[[:alpha:]]+', 
    alnum => '[[:alnum:]]+' 
);

my %res;
for my $t (keys %tests) {
    for (split(' ', $input)) {
        push(@{ $res{$t} }, $_) if (/^$tests{$t}$/i);
    }
}

Alphabet:

 /^[a-z]+$/i

What most people mean by alphanumeric:

 /^[a-z0-9]+$/i

BUT WAIT:

note: alphanumeric ex. fr43 6t$ $eed5 *jh

I didn't understand this, but judging from your comment below and the quote above, what you mean by alphanumeric might be achieved by

 /^[[:graph:]]+$/

That matches any printable ASCII characters except spaces.

Hope this has solved your problem.

If you want to recognize all valid numbers (scientific/fixed/... notation), you can let Perl do the work like this:

sub test_num {
    no warnings "all";
    $b = "$_[0]"; 
    $a = $b + 0; 
    return ($a eq $b);
}
push(@num, $tmp) if (test_num($tmp));

(The reason for the line $b = "$_[0]"; is that otherwise the original variable - $tmp - is brought into numeric context inside test_num function - a bit of undesired side-effect)