Re: Strip non-numeric

You should consider using s/\D+//g, as that's often a lot faster than s/\D//g. Here's a benchmark:

#!/usr/bin/perl

use strict;
use warnings;

use Benchmark;

my @sizes = (10, 25, 50, 100, 250, 500, 1000);
my @chars = ('A' .. 'Z', 'a' .. 'z', 0 .. 9);

our @d = map {join "" => map {$chars [rand @chars]} 1 .. $_} @sizes;

map {
    Benchmark::cmpthese timethese (-2 => {
        "simple_$sizes[$_]"   => '$_ = $::d[' . $_ . ']; s/\D//g;',
        "multiple_$sizes[$_]" => '$_ = $::d[' . $_ . ']; s/\D+//g;'
    }, 'none');
} 0 .. $#sizes
__END__
                Rate   simple_10 multiple_10
simple_10   196495/s          --        -15%
multiple_10 231225/s         18%          --
                Rate   simple_25 multiple_25
simple_25    89788/s          --        -50%
multiple_25 180650/s        101%          --
                Rate   simple_50 multiple_50
simple_50    47507/s          --        -64%
multiple_50 130727/s        175%          --
                 Rate   simple_100 multiple_100
simple_100    23206/s           --         -77%
multiple_100 103096/s         344%           --
                Rate   simple_250 multiple_250
simple_250   10488/s           --         -71%
multiple_250 36407/s         247%           --
                Rate   simple_500 multiple_500
simple_500    5046/s           --         -75%
multiple_500 20382/s         304%           --
                 Rate   simple_1000 multiple_1000
simple_1000    2528/s            --          -76%
multiple_1000 10549/s          317%            --
[download]

Abigail

Comment on Re: Strip non-numeric Select or Download Code

Replies are listed 'Best First'.
Re^3: Strip non-numeric by Aristotle (Chancellor) on Jan 14, 2003 at 09:47 UTC
In this case transliteration is really the most efficient solution though. Consider the results of adding `"xlit_$sizes[$_]" => '$_ = $::d[' . $_ . ']; tr/0-9//cd;',` to the benchmark: Rate simple_10 multiple_10 xlit_10 simple_10 86400/s -- -31% -70% multiple_10 124615/s 44% -- -57% xlit_10 292712/s 239% 135% -- Rate simple_25 multiple_25 xlit_25 simple_25 45324/s -- -49% -82% multiple_25 88062/s 94% -- -65% xlit_25 248802/s 449% 183% -- Rate simple_50 multiple_50 xlit_50 simple_50 23823/s -- -71% -89% multiple_50 82566/s 247% -- -62% xlit_50 218684/s 818% 165% -- Rate simple_100 multiple_100 xlit_100 simple_100 13397/s -- -69% -92% multiple_100 43191/s 222% -- -74% xlit_100 168434/s 1157% 290% -- Rate simple_250 multiple_250 xlit_250 simple_250 5608/s -- -71% -95% multiple_250 19639/s 250% -- -81% xlit_250 103656/s 1748% 428% -- Rate simple_500 multiple_500 xlit_500 simple_500 2832/s -- -72% -95% multiple_500 10189/s 260% -- -83% xlit_500 59072/s 1986% 480% -- Rate simple_1000 multiple_1000 xlit_1000 simple_1000 1380/s -- -77% -96% multiple_1000 5939/s 330% -- -83% xlit_1000 34457/s 2397% 480% -- [download] Esp in large data sets, transliteration screams. Makeshifts last the longest.	[reply] [d/l] [select]
Re: Strip non-numeric by Abigail-II (Bishop) on Jan 14, 2003 at 10:14 UTC
True, but my point was the pattern of `s/PAT//g`, which would benefit to be written as `s/PAT+//g`. `tr` isn't as flexible - not even in this case. `\D` follow the locale and Unicode rules when appropriate, where as the `tr` has the digits hardcoded. Abigail	[reply] [d/l] [select]
Re^5: Strip non-numeric by Aristotle (Chancellor) on Jan 14, 2003 at 10:19 UTC
Ah, I didn't think of Unicode. I briefly considered the locale awareness, but couldn't think of any case where that would change the meaning of `\d`. Makeshifts last the longest.	[reply]
Re: Strip non-numeric by Abigail-II (Bishop) on Jan 14, 2003 at 10:25 UTC
Re: Strip non-numeric by FireBird34 (Pilgrim) on Jan 14, 2003 at 04:49 UTC
Ok, thanks. Also did have one more question about this -- I didn't take into consideration about valid non-numeric (only decmial). So for example, 1a2b3.4c5d6e, I would want 123.456, not just 123456 -- tried a few combinations, but nothing yet. I'm missing something obvious I know ;) Any pointers?	[reply]
Re: Strip non-numeric by Abigail-II (Bishop) on Jan 14, 2003 at 09:46 UTC
It always helps if you are specific. Noone enjoys a game of "How do I do X?", "This is how you do X", "But I don't really want to do X, I want to do Y". So, from `1a2b3.4c5d6e`, you want `123.456`. But what if you have `1a2b.3c4d.5e6f`? What do you want then? Abigail	[reply] [d/l] [select]
Re: Strip non-numeric by Hofmator (Curate) on Jan 14, 2003 at 08:48 UTC
If I understand you correctly, you want to remove floating point numbers as well, together with normal integer numbers but not if they are part of a normal word (like 'HAL1'), don't you? Then maybe you should have a look at Regexp::Common. Together with putting whitespace around the regex you should get it to work. -- Hofmator	[reply]
Re: Strip non-numeric by FireBird34 (Pilgrim) on Jan 14, 2003 at 21:08 UTC
Basically, in any given string, I want only numeric and decimal values retained. So, basically: 1a => 1 1a.2b => 1.2 1a.2b.3c => 1.2.3 ^^ Just as those show, no matter how many decimals or numeric values, those are the only characters I want retained. Hope this clears it up just a bit.	[reply]
Re: Strip non-numeric by Abigail-II (Bishop) on Jan 14, 2003 at 21:44 UTC
So, you want to delete anything that isn't a number or a dot? Just do: `s/[^\d.]+//g;` [download] or `tr/0-9.//cd;` [download] Abigail	[reply] [d/l] [select]