Hi monks,

I'm new to perl, as well as PDL. So here's the question..

I have a matrix of size 1800x1800, and only few points have valid data(say 10000). Now, i want to interpolate(bilinear) whole matrix using the available data.

I've already implemented this using pure-perl, but due to complexity issues, i'm trying to do this using PDL

I have a few ideas in mind, but i'm too sure about them, as i don't know if i can implement the same using PDL.

Any suggestions or solutions are appreciated. Thanks in advance.

Edit:

Monk vr provided the solution in his replies. Very thankful for his responses.

Updated question

How to rescale a 2-dimensional data by interpolation, using piddles?

Solution
    use PDL;
    use PDL::Image2D;
    use PDL::IO::GD;

    my $data_pdl; #a pdl(289,145)
    my $interpolated_pdl = zeroes(21600,10800);
    bilin2n($interpolated_pdl,$data_pdl);

    my $range1 = ( $x >= 5 ) * ( $x < 10 );
    my $range2 = ( $x >= 10 ) * ( $x < 15 );
    my $range3 = $x >= 15;

    my $plotted_pdl = (     $range1 
                + 2 * $range2
                + 3 * $range3 )-> byte;

    my $palette = byte [ 
        [   0,   0,   0 ],
        [ 255,   0,   0 ],
        [   0, 255,   0 ],
        [   0,   0, 255 ]
    ];

    my $plotted_image = PDL::IO::Image->new_from_pdl($plotted_pdl,$pal
+lete);

    my $gd_image=PDL::IO::GD->new(pdl=>$plotted_image->pixels_to_pdl);

    #now all kinds of GD operations can be applied.

[download]

I'm sure there are much better ways of doing this, like directly generating a PDL::IO::GD object using PDL::IO::GD->new({ pdl => $pdl_var, lut => $lut_piddle }) but the above solution works fine.

In reply to Interpolating data using pdl by karthik248

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