Re: manipulating an array of anonymous arrays ...

You can use grep to generate a modified copy without the sub-arrays you don't want:

use strict;
use warnings;

my @matrix = (
  [48, 219, 11021],
  [72, 190, 11006],
  [203, 177, 11005],
  [301, 186, 11013],
  [309, 119, 11015],
  [309, 216, 11017],
  [309, 147, 11000],
  [343, 180, 10990],
  [346, 179, 10989],
  [451, 258, 11008],
  [838, 162, 11014]
);

# e.g. filter out all sub-arrays with x <= 309:
@matrix = grep { $_->[0] <= 309 } @matrix;

local $, = " ";
local $\ = "\n";
print @$_ for @matrix;

__END__

Output is:

48 219 11021
72 190 11006
203 177 11005
301 186 11013
309 119 11015
309 216 11017
309 147 11000
[download]

The code block you give grep gets called once for every array element with $_ as an alias for the element. In this case the elements are references to the anonymous arrays, which can be accessed by using the dereferencing operator -> like shown above.

PS: In Perl a two dimensional array, aka an array of arrays aka a matrix, uses always anonymous arrays inside. So you don't need to mentioned that explicitly with "an array of anonymous arrays".

Comment on Re: manipulating an array of anonymous arrays ... Select or Download Code

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Re^2: manipulating an array of anonymous arrays ... by chexmix (Hermit) on Apr 25, 2008 at 16:26 UTC
Thank you. I am going to try something like this with the modification that I am seeking to "toss out" the results that fell betweentwo values. I am not sure how to modify that use of grep but will have fun experimenting with it. I will try to have fun with it anyway. Working on this has involved a lot of encounters between me and my limitations (current knowledge, learning speed, and so on pretty much ad infinitum). I get lost sometimes between feeling humble ("I have so much to learn") and feeling like a deer in headlights ("I will never ever get it, my chops are those of a 3 year old and I will eventually be working at a fast food chain"). A constant diet of crow gets old, especially if like me you are vegetarian (the veggie crowcakes aren't very good, yet). :)	[reply]
Re^3: manipulating an array of anonymous arrays ... by mscharrer (Hermit) on Apr 25, 2008 at 16:33 UTC
`grep` returns all element for which the code block returns boolean true, so you have to change the code block to return true if the results are not between two values: `my @array = grep { $_->[0] <= $low \|\| $_->[0] >= $high } @array;` [download]	[reply] [d/l] [select]
Re^4: manipulating an array of anonymous arrays ... by chexmix (Hermit) on Apr 25, 2008 at 16:39 UTC
Thanks - I worked it out! :D It's a small thing, but at my level that's what I have to hold onto.	[reply]