Hello- I am working with matrices. Every matrix is implemented as a 2D array. In my code, 2D arrays are arrays of references to arrays (any other way to implement them?). When i pass a matrix to a subroutine, i pass the subroutine a reference to the matrix (also, any other way to pass such a 2D array?). The problem is that i want to dereference the reference. If i simply do: 
modify(\@matrix);
sub modify{
     $matrix_ref = shift @_;
     @new_array = @$matrix_ref
}

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This means that when i modify the @new_array, the changes will also be reflected to @matrix(right? because both @new_array and @matrix are arrays of the same set of references). To avoid this, i did the following 
for(my $row=0; $row<=$#{$matrix_ref}; $row++){
   for(my $col=0; $col<=$#{$matrix_ref->[$row]}; $col++){
         push @new_array, $matrix_ref->[$row]->[$col];
   }
}

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basically copying the contents of @matrix to @new_array. But my code passes matrices several hundred times between my different subroutines and my matrices tend to be huge. And since efficiency is quite a concern to me, i am trying to know if there's a better, more efficient way to dereference a 2D array and modify the new array without affecting the original one. If i use my way, my code is very slow. Thanks a lot for any tips

In reply to dereferencing a double array by perlrocks

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