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

Hello,

I am trying to put up a line graph but I can not get it to start displaying the graph starting at the Y axis. The graph always start at the first x tick which is one tick off to the right. Any help? Thanks.

I graph I am trying to use is at:

http://www.jonblog.uklinux.net/www/presentation/img3.html

Replies are listed 'Best First'.
Re: Help With GD::Graph::lines
by Anonymous Monk on Aug 01, 2007 at 02:17 UTC
    This is th code I am using: 
    use GD::Graph::lines;

 @data = (
      ["1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th"],
      [    1,    2,    5,    6,    3,  1.5,    1,     3,     4],
      [ sort { $a <=> $b } (1, 2, 5, 6, 3, 1.5, 1, 3, 4) ]
    );

my $graph = GD::Graph::lines->new(400,400);


$graph->set (

   x_label => 'values1',
   y_label => 'values2',
   title   => 'Correlate',
   )  or die $my_graph->error;


my $gd = $graph->plot(\@data) or die $my_graph->error;

open (IMG, '>file.png') or die $!;
binmode IMG;
print IMG $gd->png;

    [download]
    The line always start at 1st but I need it to start drawing at the origin. Any help would be appreciated.

    Thanks.

[reply]
[d/l]

      sorry, I meant to use <br> new line and not <b> for bold

      This is th code I am using: 

      use GD::Graph::lines;  
@data = (  "1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th",   
1, 2, 5, 6, 3, 1.5, 1, 3, 4,   
sort { $a <=> $b } (1, 2, 5, 6, 3, 1.5, 1, 3, 4)  ); 
my $graph = GD::Graph::lines->new(400,400); 
$graph->set (  
x_label => 'values1',  
y_label => 'values2',  
title => 'Correlate',  
) or die $my_graph->error; 
my $gd = $graph->plot(\@data) or die $my_graph->error; 
open (IMG, '>file.png') or die $!; 
binmode IMG; 
print IMG $gd->png;

      [download]

      The line always start at 1st but I need it to start drawing at the origin. Any help would be appreciated. Thanks.

      Code tags added by GrandFather

[reply]
[d/l]

        Try prefixing your value sets with zeros. 

        use GD::Graph::lines;

@data = (
    [ '0', "1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th", ],
    [ 0, 1, 2, 5, 6, 3, 1.5, 1, 3, 4, ],
    [ 0, sort { $a <=> $b } (1, 2, 5, 6, 3, 1.5, 1, 3, 4) ],
);

my $graph = GD::Graph::lines->new(400,400);
$graph->set (
    x_label => 'values1',
    y_label => 'values2',
    title => 'Correlate',
) or die $!;

my $gd = $graph->plot(\@data) or die $!;

open (IMG, '>file.png') or die $!;
binmode IMG;
print IMG $gd->png;
close IMG;

        [download]

        Also, please read the formatting guidelines next time you post.

        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]
        Guess it's got to do with the type of data you use. 1st is only the first appearance of the data. Therefor it'll not start at zero. Maybe a bar chart is more natural?

        A site you might think is interesting:
        http://gdgraph.com/samples/sample11.html

        Gert
[reply]

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