sort on numeric portion of key 1

[adumitrescu]

Hello,
The items in my array all looks like "nnn/xxx" where nnn is a number with 1 to 5 digits, and xxx is a string. I wish to sort this array numerically. Using sort {$a <=> $b} %array does sort as desired, but outputs a TON of warnings about my argument not being numeric. I don't want to just hide the warnings - I would rather tune my sort comparison to be more intelligent (only compare the piece up to but not including the slash.
Thanks.

 

[MillerH]

First of all, %array is not an array but a hash. I'm assuing that you either want "keys %hash" or "@array". I'll let you decide which is appropriate.

Secondly, all you need to do is a Schwartzian transform:

http://en.wikipedia.org/wiki/Schwartzian_transform

Here is an example that does what you require:

my @array = ('5/aaa', '12/bbb', '4/ccc');

my @sorted = map { $_->[0] } sort { $a->[1] <=> $b->[1] } map { [$_, m/(\d+)/] } @array;

# Equals: 4/ccc,5/aaa,12/bbb

 

[adumitrescu]

Thanks MillerH,
This does exactly as I had hoped - awesome!

p.s. Sorry for the misunderstanding - My old Perl book doesn't use the term 'hash' for %array, but rather Associative Array.

Cheers - The Foreign Kid

 

[KevinADC]

cutefez, make sure to check the perl faqs too.

How do I sort columns/fields of mixed data?

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- Kevin, perl coder unexceptional!