Perl Graph

[JackTheRussel]

Hi.

I would like to make some charts and graphs in perl.

I have no clue where to start. I noticed this example in internet, but when I run this program nothing happens.

How would I get out some png or jpeg picture by using this example ?

#!/usr/bin/perl

use GD::Graph::bars;

@data = ( 
    ["1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th"],
    [   11,   12,   15,   16,    3,  1.5,    1,     3,     4],
    [    5,   12,   24,   15,   19,    8,    6,    15,    21],
    [    12,   3,    1,   5,    12,    9,   16,    25,    11],
);

$my_graph = new GD::Graph::bars( );
$my_graph->set( 
        x_label => 'X Label',
        y_label => 'Y label',
        title => 'Stacked Bars (incremental)',
        y_max_value => 50,
        y_tick_number => 10,
        y_label_skip => 2,
        cumulate => 1,
);

$my_graph->set_legend( qw(offset increment more));
my $gd = $my_graph->plot(\@data);

From here I noticed this example.

http://bioportal.weizmann.ac.il/course/prog/graphics/

 

[ishnid]

You can do it like this:

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

 

[JackTheRussel]

Yes..

Thanks ishnid!

 

[JackTheRussel]

BTW. Does anyone know somekind tutorial pages where are information about Perl-graphs.

Example now I would need information how I can read data from file. I don't want to read data from @table. (example which is above).


And Can I somehow make reasonable pictures where I have time and value data like this:

(notice that time-perioids are really tiny.)

       [time]      [value]
2007-02-09 13:06:04 1.487
2007-02-09 13:06:05 0.198
2007-02-09 13:06:05 0.167
2007-02-09 13:06:09 8.307
2007-02-09 13:06:09 3.631
2007-02-09 13:11:28 1.491
2007-02-09 13:11:40 0.178
2007-02-09 13:11:40 0.403
2007-02-09 13:11:40 2.513
2007-02-09 13:11:40 1.401
2007-02-09 13:13:32 1.5
2007-02-09 13:13:44 0.18
2007-02-09 13:13:44 0.269
2007-02-09 13:13:48 2.63
2007-02-09 13:13:48 1.829
2007-02-09 13:31:26 1.48
2007-02-09 13:31:38 0.181
2007-02-09 13:31:38 0.27
2007-02-09 13:31:42 2.03
2007-02-09 13:31:42 1.354
2007-02-09 13:33:10 1.494
2007-02-09 13:33:23 0.203
2007-02-09 13:33:23 0.166
2007-02-09 13:33:26 2.541
2007-02-09 13:33:26 1.851
2007-02-09 13:35:56 1.494
2007-02-09 13:36:09 0.176
2007-02-09 13:36:09 0.271

 

[Kirsle]

open (DATA, "table.txt");
my @data = <DATA>;
close (DATA);
chomp @data;

my $arrayref = [
   [ "Date", "Time", "Value" ],
];

foreach my $line (@data) {
   my ($date,$time,$value) = split(/\s+/, $line, 3);
   push (@{$arrayref}, [
      $date, $time, $value
   ]);
}

# $arrayref should look like this afterward...
$arrayref = [
   [ "Date",       "Time",     "Value" ],
   [ "2007-02-09", "13:06:04", "1.487" ],
   [ "2007-02-09", "13:06:05", "0.198" ],
   [ "2007-02-09", "13:06:05", "0.167" ],
   #etc......
];

You wouldn't find a tutorial about reading from a file and manipulating data structures when looking for a tutorial on graphing; you'd want to look up tutorials on reading from a file and manipulating data structures. Graphing comes after the author assumes you know how to get the information you want to graph to begin with. ;-)

-------------
Cuvou.com | The NEW Kirsle.net

 

[JackTheRussel]

Kirsie thanks..

Hate to ask stupid questions, but I'll have to.

Do I have to use @data or $arrayref when I plot my picture ?

I get error when I try to plot my picture

my $gd = $my_graph->plot(\@data);

---> Can't call method "png" on an undefined value

Or...

my $gd = $my_graph->plot(\$arrayref);

---> Can't call method "png" on an undefined value

 

[TorontoJim]

Here is a library that will create bar graphs, line graphs and very simple pie charts. It uses only JavaScript1.2 so should be good for most of todays browsers:

http://www.geocities.com/james_melanson/JSOOP/jsgraph.html

 

[Kirsle]

my $gd = $my_graph->plot($arrayref);

Try removing the backslash, since $arrayref is already a reference to an array (using \@data would've made a reference to @data)

I didn't look up how GD::Graph works, but the code I posted turns your data into a structure similar to the example you posted above

@data = (
    ["1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th"],
    [   11,   12,   15,   16,    3,  1.5,    1,     3,     4],
    [    5,   12,   24,   15,   19,    8,    6,    15,    21],
    [    12,   3,    1,   5,    12,    9,   16,    25,    11],
);

-------------
Cuvou.com | The NEW Kirsle.net

 

[JackTheRussel]

Thank for you help Kirsie.

Now it works !


TorontoJim:

Thanks for advice, but I don't have use for that program.
(browser use).