in reply to Fast Matrix Load

Well, you don't tell us anything about the file, but if it's comma delimited, then perhaps this: 
#!/usr/bin/perl -w
use strict;
use warnings;

# create array ref and count
my $matrix=();
my $i=0;

open PROFILES, 'profile/profile.db' or die $!;
while (<PROFILES>) {
  chomp;

  # add array as array ref to array ref
  @{$matrix->[$i]} =  split /\t/; 
  $i++;
}
close(PROFILES);

# access referenced data like this

print $matrix->[1]->[6];

# (7th element of 2nd row generally :)
# should start at 0,0

exit(0);

[download]

cLive ;-)

Update: since you've added more info, I've updated above to reflect your existing code..

--
seek(JOB,$$LA,0);

Replies are listed 'Best First'.
Re: (cLive ;-) Re: Fast Matrix Load
by Evanovich (Scribe) on Feb 17, 2002 at 03:43 UTC
    Well, that might help, except that there's one caveat. I'm passing this matrix to a C routine. Here's how it works, once I build the matrix @matrix as shown earlier: 
    anglecast (@matrix);
sub anglecast (\@) {
    my $avMatrix = shift (@_); 
    my $packedMatrix= "";
    my @recycleBin;
    my $width= @{$avMatrix->[0]};
    for my $avRow(@$avMatrix) {
 $width= @$avRow if @$avRow<$width;
 my $packedRow= pack("f$width", @$avRow);
 push @recycleBin, \$packedRow;
 $packedMatrix .= pack("P", $packedRow);
    }
    return CAST(0+@$avMatrix, $width, $packedMatrix);
 }

Anyone know how to modify this if I want to use references?  Or maybe 
+there's a more efficient way to load a matrix?  Thanks again, Evan

    [download]
[reply]
[d/l]
      The quickest solution I can think of (without trying to understand your code), is to dereference the array as you send it to the sub, ie: 
      anglecast (@{$matrix});

      [download]

      cLive ;-)

      --
      seek(JOB,$$LA,0);

[reply]
[d/l]

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