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

Hello!

I was wondering if anyone knew a way to display data labels (as the ones in the legend) directly next or instead of the points in Chart::Points. I looked through the options but there does not seem to be one for this. It seems a bit weird, as I would have thought it's a common way to display data.

Thanks for your help

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Re: Data labels for Chart::Points
by poj (Abbot) on Sep 11, 2013 at 16:28 UTC
    You could use imagemap_dump together with GD, for example ; 
    #!perl
use strict;
use Data::Dump 'pp';
use Chart::Points;
use GD;
my $obj = Chart::Points->new ( 400,300 );
$obj->{'imagemap'}=1;
my @labels = ('A','B','C');
$obj->set ('legend_labels' => \@labels);
$obj->add_pt ('foo', 1,3,2);
$obj->add_pt ('bar', 4,5,6);

# create GD image
my $img = GD::Image->new($obj->scalar_png);
my $imagemap_data = $obj->imagemap_dump();
#pp $imagemap_data;

# add labels
my $black = $img->colorAllocate(0,0,0); 
for my $i (1..3){
  for my $j (0..1){
    my $text = $labels[$i-1];
    my ($x,$y)  = @{$imagemap_data->[$i][$j]};
    $img->string(gdSmallFont,$x-10,$y-10,$text,$black);
  }
}

open (PNG,'>','chart.png') or die "$!";
binmode PNG;
print PNG $img->png;
close PNG;

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    poj
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      It works perfectly! Thanks a lot.

[reply]
      How can I do the same "print data labels" when I use 3d charts? Thanks
[reply]
        Which chart module are you using ?
        poj
[reply]

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