--- loncom/xml/lonplot.pm	2008/11/24 17:17:52	1.149
+++ loncom/xml/lonplot.pm	2011/07/04 09:25:13	1.153
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.149 2008/11/24 17:17:52 jms Exp $
+# $Id: lonplot.pm,v 1.153 2011/07/04 09:25:13 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -455,7 +455,7 @@ my %tic_defaults =
 	 },         
      );
 
-my @axis_edit_order = ('color','xmin','xmax','ymin','ymax','xformat', 'yformat');
+my @axis_edit_order = ('color','xmin','xmax','ymin','ymax','xformat', 'yformat', 'xzero', 'yzero');
 my %axis_defaults = 
     (
      color   => {
@@ -503,11 +503,26 @@ my %axis_defaults =
      yformat      => {
          default     => 'on',
          test        => sub {$_[0]=~/^(on|off|\d+(f|F|e|E))$/},
-         description => 'X-axis number formatting',
+         description => 'Y-axis number formatting',
          edit_type   => 'choice',
          choices     => ['on', 'off', '2e', '2f'],
          },
-
+     
+     xzero => {
+     	default => 'off',
+     	test	=> sub {$_[0]=~/^(off|line|thick-line|dotted)$/},
+     	description => 'Show x-zero (y=0) axis',
+     	edit_type  => 'choice',
+     	choices	=> ['off', 'line', 'thick-line', 'dotted'],
+     	},
+     
+     yzero => {
+     	default => 'off',
+     	test	=> sub {$_[0]=~/^(off|line|thick-line|dotted)$/},
+     	description => 'Show y-zero (x=0) axis',
+     	edit_type  => 'choice',
+     	choices	=> ['off', 'line', 'thick-line', 'dotted'],
+     	},
      );
 
 my @curve_edit_order = ('color','name','linestyle','linewidth','linetype','pointtype','pointsize','limit');
@@ -619,6 +634,8 @@ sub end_gnuplot {
 	('title','xlabel','ylabel','key','axis','label','curve'));
     my $result = '';
     my $randnumber;
+    my $tmpdir =LONCAPA::tempdir(); # Where temporary files live:
+
     # need to call rand everytime start_script would evaluate, as the
     # safe space rand number generator and the global rand generator 
     # are not separate
@@ -630,7 +647,6 @@ sub end_gnuplot {
 	&check_inputs(); # Make sure we have all the data we need
 	##
 	## Determine filename
-	my $tmpdir = '/home/httpd/perl/tmp/';
 	my $filename = $env{'user.name'}.'_'.$env{'user.domain'}.
 	    '_'.time.'_'.$$.$randnumber.'_plot';
 	## Write the plot description to the file
@@ -651,7 +667,7 @@ ENDIMAGE
 	    #might be inside the safe space, register the URL for later
 	    &Apache::lonxml::register_ssi("/cgi-bin/plot.gif?file=$filename.data&output=eps");
 	    $result  = "%DYNAMICIMAGE:$Apache::lonplot::plot{'width'}:$Apache::lonplot::plot{'height'}:$Apache::lonplot::plot{'texwidth'}\n";
-	    $result .= '\graphicspath{{/home/httpd/perl/tmp/}}'."\n";
+	    $result .= '\graphicspath{{'.$tmpdir.'}}'."\n";
 	    $result .= '\includegraphics[width='.$Apache::lonplot::plot{'texwidth'}.' mm]{'.&unescape($filename).'.eps}';
 	}
     } elsif ($target eq 'edit') {
@@ -1440,7 +1456,7 @@ sub start_data {
 	}
 	# complain if the number of data points is not the same as
 	# in previous sets of data.
-	if (($curves[-1]->{'data'}) && ($#data != $#{@{$curves[-1]->{'data'}->[0]}})){
+	if (($curves[-1]->{'data'}) && ($#data != $#{$curves[-1]->{'data'}->[0]})){
 	    &Apache::lonxml::warning
 		('Number of data points is not consistent with previous '.
 		 'number of data points');
@@ -1594,7 +1610,7 @@ sub write_gnuplot_file {
 	}
 	$gnuplot_input .= ' "'.$font_properties->{'printname'}.'" ';
 	$gnuplot_input .= $fontsize;
-	$gnuplot_input .= "\nset output \"/home/httpd/perl/tmp/".
+	$gnuplot_input .= "\nset output \"".$tmpdir.
 	    &unescape($filename).".eps\"\n";
 	$gnuplot_input .= "set encoding iso_8859_1\n"; # Get access to extended font.
 
@@ -1735,6 +1751,26 @@ sub write_gnuplot_file {
         }
 	$gnuplot_input .= "set xrange \[$axis{'xmin'}:$axis{'xmax'}\]\n";
 	$gnuplot_input .= "set yrange \[$axis{'ymin'}:$axis{'ymax'}\]\n";
+		if ($axis{'xzero'} ne 'off') {
+			$gnuplot_input .= "set xzeroaxis ";
+			if ($axis{'xzero'} eq 'line' || $axis{'xzero'} eq 'thick-line') {
+				$gnuplot_input .= "lt -1 ";
+				if ($axis{'xzero'} eq 'thick-line') {
+					$gnuplot_input .= "lw 3 ";
+				}
+			}
+			$gnuplot_input .= "\n";
+		}
+		if ($axis{'yzero'} ne 'off') {
+			$gnuplot_input .= "set yzeroaxis ";
+			if ($axis{'yzero'} eq 'line' || $axis{'yzero'} eq 'thick-line') {
+				$gnuplot_input .= "lt -1 ";
+				if ($axis{'yzero'} eq 'thick-line') {
+					$gnuplot_input .= "lw 3 ";
+				}
+			}
+			$gnuplot_input .= "\n";
+		}
     }
     # Key
     if (%key) {