Dear Monks (and especially Tye, who was very kind in helping me on this task earlier): I am trying to pass a large 2-D float array from Perl to C in order to perform some mathematical functions on it. At the suggestion of Tye, I was told to pack the Perl array and send it through, and then recast a matrix in C. I am not very experienced in C (or much in Perl for that matter, but more so), and thus I'm having some trouble printing the values in the test array I've made. Here is the code I've put together (at the bottom I used the Perl module Inline to put the XSUB together automatically): 

#! /usr/bin/perl -w
use strict;

use Inline C;

sub MyFunc(\@);

my $ref1 = [1,2,3,4,5];
my $ref2 = [6,7,8,9,10];
my @matrix;

for (0..$#{$ref1}) {
    $matrix[0]->[$_] = ${$ref1}[$_];
}

$_ = 0;
for (0..$#{$ref2}) {
    $matrix[1]->[$_] = ${$ref2}[$_];
}


MyFunc(@matrix);

sub MyFunc (\@) {
    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", $packedRow);
    }
    return getangles(0+@$avMatrix, $width, $packedMatrix);
}




__END__
__C__

    int getangles(int rows, int cols, char* packedMatrix) {
 int **M = (int **)packedMatrix;
 printf("Here I want the first entry of the matrix: %d", M);

    }

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This seems to return a long number, not the desired number "1." Any suggestions?

In reply to Sending packed arrays from Perl to C by Evanovich

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