Re: get a column out of a 2d array

On 10/3/07, Mahurshi Akilla <mahurshi@xxxxxxxxx> wrote:

is there an easy way (without iterating through the array) to get a
specified column out of a 2d array?

There is no way in general, easy or hard, to get a column out of an
array in Perl without using iteration, even if the iteration is hidden
inside a map, foreach, or something similar. So, your answer is "no".

i know you can get it with rows using ( $my2ndrowref = @array[1] ) but
i don't want to transpose all my data right now for this.

I think you mean something like this:

my @second_row = @{ $array[1] };
print "Second row: @second_row\n";

But now you want a column, instead of a row. Well, if there actually
is a column there (we'll assume your data is rectangular), it's easy
to extract a copy with map:

my @second_col = map $_->[1], @array;
print "Second column: @second_col\n";

That's a copy, instead of the original data. If you want to modify it,
there's probably a better way to do that.

Does that do anything good for you? Good luck with it!

--Tom Phoenix
Stonehenge Perl Training
.

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