#!/usr/bin/perl # # $Id: graph.png,v 1.29 2003/10/27 21:21:08 matthew Exp $ # # Copyright Michigan State University Board of Trustees # # This file is part of the LearningOnline Network with CAPA (LON-CAPA). # # LON-CAPA is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # LON-CAPA is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with LON-CAPA; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # # /home/httpd/cgi-bin/graph.gif # # http://www.lon-capa.org/ # # The LearningOnline Network with CAPA # # A CGI script that dynamically outputs a graphical chart for lonstatistics. # #### =pod =head1 NAME graph.png =head1 SYNOPSIS produces plots based on input =head1 DESCRIPTION graph.png is a cgi-bin script which produces plots based on input data. The query string is expected to be as follows (without whitespace): escape(Plot title) & escape(X label)& escape(Y label) & Maximum Y value & Number of bars & $data1 & $data2 $data1 and $data2 are expected to be comma seperated lists of numbers. escape( value ) means the values must be run through lonnet::escape. =cut use strict; use lib '/home/httpd/lib/perl'; use GD::Graph::bars; use GD::Graph::lines; use GD::Graph::colour; use GD::Graph::Data; use LONCAPA::loncgi(); sub unescape { my $str=shift; $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg; return $str; } sub error { my ($error) = @_; my $Str = <<"END"; Content-type: text/html
There was an error producing the graph you requested.
$error
END return $Str; } my $id = $ENV{'QUERY_STRING'}; # # &get_env($name,$default) sub get_env { my $key = 'cgi.'.$id.'.'.(shift()); return shift if (! exists($ENV{$key})); return $ENV{$key}; } if (! &LONCAPA::loncgi::check_cookie_and_load_env()) { print <