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vroom has asked for the wisdom of the Perl Monks concerning the following question:

I want to take a long string of text and split it into a two-dimensional array of $width x $height. I know of several ways to do this but none of them are as quick and dirty as I'd like them to be? Any suggestions?

Some clarification: I want to read in the data from a bitmap say a PGM file where each 'character' is a pixel. First I'm going to break the header off the string, after that I want to split the data portion into a 2-D array of $widthx$height. I know of ways to do this but am looking for something really quick and clever.
  • Comment on How can I cleanly split a string of text into a two-dimensional array

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Re: How can I cleanly split a string of text into a two-dimensional array
by chromatic (Archbishop) on Apr 01, 2000 at 10:58 UTC
    How about: 
    my $data = "whatever";
my @pixels = [][];
for (my $i = 1; $i < $height; $i++) {
    (@pixels[$i][1 .. $width], $data) = split('', $data, $width);
}

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Re: How can I cleanly split a string of text into a two-dimensional array
by fenonn (Chaplain) on Jun 07, 2001 at 23:21 UTC
    Well if there is a char that marks the end of a row (new line for example) you could try something like this. 
    @array = map { [split//] } (split/\n/,$string);

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Re: How can I cleanly split a string of text into a two-dimensional array
by BBQ (Curate) on Dec 24, 1999 at 03:03 UTC
    I agree with root. I guess giving a purpose for the split might be more enlightning. What do you want the two arrays do? What should they control? Are we talking bitmaps here?
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Re: How can I cleanly split a string of text into a two-dimensional array
by da w00t (Sexton) on Dec 30, 1999 at 02:24 UTC
    would something liek this work? 
    #!/usr/bin/perl
use Data::Dumper;

open(FILE,"<xpm-pic");
$row=-1;$col=-1;
while (<FILE>) {
  chomp;
  $row++;
  $col=-1;
  foreach $char (split //) {
    $col++;$pix[$row][$col]=$char;
  }
}
print Dumper(\@pix);

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Re: How can I cleanly split a string of text into a two-dimensional array
by Anonymous Monk on Dec 23, 1999 at 03:56 UTC
    I'm not sure the problem is clear. What do you want each element of an array to be? You could always use nested Foreach loops, of course...
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Re: How can I cleanly split a string of text into a two-dimensional array
by nothingmuch (Priest) on Jan 14, 2005 at 17:07 UTC 
    map { [ split '', $_ ] }
    unpack join(" ", ("a$width") x $height), $string;

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    -nuffin
    zz zZ Z Z #!perl
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