--- loncom/xml/lonplot.pm	2008/06/02 10:49:47	1.144
+++ loncom/xml/lonplot.pm	2014/07/09 15:17:32	1.152.6.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.144 2008/06/02 10:49:47 foxr Exp $
+# $Id: lonplot.pm,v 1.152.6.1 2014/07/09 15:17:32 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -26,6 +26,9 @@
 # http://www.lon-capa.org/
 #
 
+
+
+
 package Apache::lonplot;
 
 use strict;
@@ -57,6 +60,8 @@ BEGIN {
 }
 
 
+=pod
+
 ## 
 ## Description of data structures:
 ##
@@ -88,6 +93,8 @@ BEGIN {
 ##                                                               ##
 ###################################################################
 
+=cut
+
 my $max_str_len = 50;    # if a label, title, xlabel, or ylabel text
                          # is longer than this, it will be truncated.
 
@@ -448,7 +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   => {
@@ -496,11 +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');
@@ -757,6 +779,7 @@ sub get_font {
 	$selected_font = $font_properties{$Apache::lonplot::plot{'fontface'}};
     }
     if ($target eq 'tex' && defined($Apache::lonplot::plot{'texfont'})) {
+#	$selected_font = $font_properties{'classic'};
 	$size = $Apache::lonplot::plot{'texfont'};
     }
     return ($size, $selected_font);
@@ -1050,7 +1073,7 @@ my %lookup =
       '(rdquo|#8221)'  => {'tex' => '\42',   'web' => "\x{201d}"}, # Right double quote.
       '(bdquo|#8222)'  => {'tex' => ',',              'web' => "\x{201e}"}, # Double low-9 quote.
       '(dagger|#8224)' => {'tex' => '+',   'web' => "\x{2020}"}, # Is this a dagger I see before me now?
-      '(Dagger|#8225)' => {'tex' => '\261}',   'web' => "\x{2021}"}, # it's handle pointing towards my heart?
+      '(Dagger|#8225)' => {'tex' => '\261',   'web' => "\x{2021}"}, # it's handle pointing towards my heart?
       '(bull|#8226)'   => {'tex' => '\267',           'web' => "\x{2022}"}, # Bullet.
       '(hellep|#8230)' => {'tex' => '{/Symbol \274}',   'web' => "\x{2026}"}, # Ellipses.
       '(permil|#8240)' => {'tex' => '%_o',            'web' => "\x{2031}"}, # Per mille.
@@ -1091,10 +1114,11 @@ my %lookup =
       '(empty|#8709)'   => {'tex' => '{/Symbol \306}',  'web' => "\x{2205}"}, # Null set.
       '(nabla|#8711)'   => {'tex' => '{/Symbol \321}',  'web' => "\x{2207}"}, # Gradient e.g.
       '(isin|#8712)'    => {'tex' => '{/Symbol \316}',  'web' => "\x{2208}"}, # Element of the set.
+      '(notin|#8713)'   => {'tex' => '{/Symbol \317}',  'web' => "\x{2209}"}, # Not an element of
       '(ni|#8715)'      => {'tex' => '{/Symbol \47}',   'web' => "\x{220b}"}, # Contains as a member
       '(prod|#8719)'    => {'tex' => '{/Symbol \325}',  'web' => "\x{220f}"}, # Product 
       '(sum|#8721)'     => {'tex' => '{/Symbol \345}',  'web' => "\x{2211}"}, # Sum of.
-      '(minus|#8722)'   => {'tex' => '-',               'web' => "\x{2212}"}, # - sign.
+      '(minus|#8722)'   => {'tex' => '{/Symbol \55}',   'web' => "\x{2212}"}, # - sign.
       '(lowast|#8727)'  => {'tex' => '*',               'web' => "\x{2217}"}, # * 
       '(radic|#8730)'   => {'tex' => '{/Symbol \326}',  'web' => "\x{221a}"}, # Square root. 
       '(prop|#8733)'    => {'tex' => '{/Symbol \265}',  'web' => "\x{221d}"}, # Proportional to.
@@ -1105,10 +1129,15 @@ my %lookup =
       '(cap|#8745)'     => {'tex' => '{/Symbol \307}',  'web' => "\x{2229}"}, # Set intersection.
       '(cup|#8746)'     => {'tex' => '{/Symbol \310}',  'web' => "\x{222a}"}, # Set union.
       '(int|8747)'      => {'tex' => '{/Symbol \362}',  'web' => "\x{222b}"}, # Integral.
-      '(there4|#8756)'  => {'tex' => '{/Symbol \134}',  'web' => "\x{2234}"}, # Therefore triple dots.
-      '(sim|#8764)'     => {'tex' => '~',               'web' => "\x{223c}"}, # Simlar to.
-      '(cong|#8773)'    => {'tex' => '{/Symbol \100}',  'web' => "\x{2245}"}, # Congruent to/with.
-      '(asymp|#8776)'   => {'tex' => '{/Symbol \278}',  'web' => "\x{2248}"}, # Asymptotic to.
+
+      # Some gnuplot guru will have to explain to me why the next three
+      # require the extra slashes... else they print very funkily.
+
+      '(there4|#8756)'  => {'tex' => '{/Symbol \\\134}',  'web' => "\x{2234}"}, # Therefore triple dots.
+      '(sim|#8764)'     => {'tex' => '\\\176',               'web' => "\x{223c}"}, # Simlar to.
+      '(cong|#8773)'    => {'tex' => '{/Symbol \\\100}','web' => "\x{2245}"}, # Congruent to/with.
+
+      '(asymp|#8776)'   => {'tex' => '{/Symbol \273}',  'web' => "\x{2248}"}, # Asymptotic to.
       '(ne|#8800)'      => {'tex' => '{/Symbol \271}',  'web' => "\x{2260}"}, # not equal to.
       '(equiv|#8801)'   => {'tex' => '{/Symbol \272}',  'web' => "\x{2261}"}, # Equivalent to.
       '(le|8804)'       => {'tex' => '{/Symbol \243}',  'web' => "\x{2264}"}, # Less than or equal to.
@@ -1129,8 +1158,12 @@ my %lookup =
       '(rceil|8969)'    => {'tex' => '{/Symbol \371}',  'web' => "\x{2309}"}, # Right ceiling.
       '(lfloor|8970)'   => {'tex' => '{/Symbol \353}',  'web' => "\x{230a}"}, # Left floor.
       '(rfloor|8971)'   => {'tex' => '{/Symbol \373}',  'web' => "\x{230b}"}, # Right floor.
-      '(lang|9001)'     => {'tex' => '{/Symbol \341}',  'web' => "\x{2329}"}, # Left angle bracket.
-      '(rang|9002)'     => {'tex' => '{/Symbol \361}',  'web' => "\x{232a}"}, # Right angle bracket.
+
+      # The gnuplot png font evidently does not have the big angle brackets at
+      # positions 0x2329, 0x232a so use ordinary brackets.
+
+      '(lang|9001)'     => {'tex' => '{/Symbol \341}',  'web' => '<'}, # Left angle bracket.
+      '(rang|9002)'     => {'tex' => '{/Symbol \361}',  'web' => '>'}, # Right angle bracket.
 
       # Gemoetric shapes.
 
@@ -1351,6 +1384,7 @@ sub start_function {
         my $function = &Apache::lonxml::get_all_text("/function",$parser,
 						     $style);
 	$function = &Apache::run::evaluate($function,$safeeval,$$parstack[-1]);
+        $function=~s/\^/\*\*/gs;
 	$curves[-1]->{'function'} = $function; 
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Gnuplot compatible curve function');
@@ -1421,7 +1455,7 @@ sub start_data {
 	}
 	# complain if the number of data points is not the same as
 	# in previous sets of data.
-	if (($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');
@@ -1647,8 +1681,12 @@ sub write_gnuplot_file {
     $gnuplot_input .= "set samples $Apache::lonplot::plot{'samples'}\n";
     # title, xlabel, ylabel
     # titles
-    my $extra_space_x = ($xtics{'location'} eq 'axis') ? ' 0, -0.5 ' : '';
-    my $extra_space_y = ($ytics{'location'} eq 'axis') ? ' -0.5, 0 ' : '';
+    my $offset;
+    if ($version >= 4.4) {
+        $offset = 'offset ';
+    }
+    my $extra_space_x = ($xtics{'location'} eq 'axis') ? ' '.$offset.'0, -0.5 ' : '';
+    my $extra_space_y = ($ytics{'location'} eq 'axis') ? ' '.$offset.'-0.5, 0 ' : '';
 
     if ($target eq 'tex') {
 	$gnuplot_input .= "set title  \"$title\"          font \"".$font_properties->{'printname'}.",".$fontsize."pt\"\n" if (defined($title)) ;
@@ -1665,20 +1703,36 @@ sub write_gnuplot_file {
 	$gnuplot_input .= ( $xtics{'mirror'} eq 'on'?"mirror ":"nomirror ");
 	$gnuplot_input .= "$xtics{'start'}, ";
 	$gnuplot_input .= "$xtics{'increment'}, ";
-	$gnuplot_input .= "$xtics{'end'}\n";
+	$gnuplot_input .= "$xtics{'end'} ";
+	if ($target eq 'tex') {
+	    $gnuplot_input .= 'font "Helvetica,22"';     # Needed in iso 8859-1 enc.
+	}
+	$gnuplot_input .= "\n";
         if ($xtics{'minorfreq'} != 0) {
             $gnuplot_input .= "set mxtics ".$xtics{'minorfreq'}."\n";
         } 
+    } else {
+	if ($target eq 'tex') {
+	    $gnuplot_input .= 'set xtics font "Helvetica,22"'."\n"; # needed in iso 8859-1 enc
+	}
     }
     if (%ytics) {    
 	$gnuplot_input .= "set ytics $ytics{'location'} ";
 	$gnuplot_input .= ( $ytics{'mirror'} eq 'on'?"mirror ":"nomirror ");
 	$gnuplot_input .= "$ytics{'start'}, ";
 	$gnuplot_input .= "$ytics{'increment'}, ";
-        $gnuplot_input .= "$ytics{'end'}\n";
+        $gnuplot_input .= "$ytics{'end'} ";
+        if ($target eq 'tex') {
+            $gnuplot_input .= 'font "Helvetica,22"'; # Needed in iso-8859-1 encoding.
+        }
+        $gnuplot_input .= "\n";
         if ($ytics{'minorfreq'} != 0) {
             $gnuplot_input .= "set mytics ".$ytics{'minorfreq'}."\n";
         } 
+    } else {
+	if ($target eq 'tex') {
+	    $gnuplot_input .= 'set ytics font "Helvetica,22"'."\n"; # Needed for iso 8859-1 enc.
+	}
     }
     # axis
     if (%axis) {
@@ -1700,6 +1754,26 @@ 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) {
@@ -1988,3 +2062,118 @@ sub insert_data {
 __END__
 
 
+=head1 NAME
+
+Apache::lonplot.pm
+
+=head1 SYNOPSIS
+
+XML-based plotter of graphs
+
+This is part of the LearningOnline Network with CAPA project
+described at http://www.lon-capa.org.
+
+
+=head1 SUBROUTINES (parsing and edit rendering)
+
+=over
+
+=item start_gnuplot()
+
+=item end_gnuplot()
+
+=item start_xtics()
+
+=item end_xtics()
+
+=item start_ytics()
+
+=item end_ytics()
+
+=item get_font()
+
+=item start_key()
+
+=item end_key()
+
+=item parse_label()
+
+=item replace_entities()
+
+=item start_title()
+
+=item end_title()
+
+=item start_xlabel()
+
+=item end_xlabel()
+
+=item start_ylabel()
+
+=item end_label()
+
+=item start_curve()
+
+=item end_curve()
+
+=item start_function()
+
+=item end_function()
+
+=item start_data()
+
+=item end_data()
+
+=item start_axis()
+
+=item end_axis
+
+=back
+
+=head1 SUBROUTINES (Utility)
+
+=over
+
+=item set_defaults()
+
+=item get_attributes()
+
+=item write_gnuplot_file()
+
+=item check_inputs()
+
+=item edit_attributes()
+
+=back
+
+=head1 SUBROUTINES (Insertion functions for editing plots)
+
+=over
+
+=item insert_gnuplot()
+
+=item insert_tics()
+
+=item insert_xtics()
+
+=item insert_key()
+
+=item insert_axis()
+
+=item insert_title()
+
+=item insert_xlabel()
+
+=item insert_ylabel()
+
+=item insert_label()
+
+=item insert_curve()
+
+=item insert_function()
+
+=item insert_data()
+
+=back
+
+=cut