--- loncom/xml/lonplot.pm	2002/03/22 16:56:37	1.62
+++ loncom/xml/lonplot.pm	2004/03/08 17:31:37	1.95
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.62 2002/03/22 16:56:37 matthew Exp $
+# $Id: lonplot.pm,v 1.95 2004/03/08 17:31:37 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -34,6 +34,8 @@
 package Apache::lonplot;
 
 use strict;
+use warnings FATAL=>'all';
+no warnings 'uninitialized';
 use Apache::File;
 use Apache::response;
 use Apache::lonxml;
@@ -99,12 +101,12 @@ my $real_test      =
     sub {$_[0]=~s/\s+//g;$_[0]=~/^[+-]?\d*\.?\d*([eE][+-]\d+)?$/};
 my $pos_real_test  =
     sub {$_[0]=~s/\s+//g;$_[0]=~/^[+]?\d*\.?\d*([eE][+-]\d+)?$/};
-my $color_test     = sub {$_[0]=~s/\s+//g;$_[0]=~/^x[\da-f]{6}$/};
+my $color_test     = sub {$_[0]=~s/\s+//g;$_[0]=~/^x[\da-fA-F]{6}$/};
 my $onoff_test     = sub {$_[0]=~/^(on|off)$/};
 my $key_pos_test   = sub {$_[0]=~/^(top|bottom|right|left|outside|below| )+$/};
 my $sml_test       = sub {$_[0]=~/^(small|medium|large)$/};
 my $linestyle_test = sub {exists($linestyles{$_[0]})};
-my $words_test     = sub {$_[0]=~s/\s+/ /g;$_[0]=~/^([\w\(\)]+ ?)+$/};
+my $words_test     = sub {$_[0]=~s/\s+/ /g;$_[0]=~/^([\w~!\@\#\$\%^&\*\(\)-=_\+\[\]\{\}:\;\'<>,\.\/\?\\]+ ?)+$/};
 
 ###################################################################
 ##                                                               ##
@@ -112,7 +114,8 @@ my $words_test     = sub {$_[0]=~s/\s+/
 ##                                                               ##
 ###################################################################
 my @gnuplot_edit_order = 
-    qw/bgcolor fgcolor height width font transparent grid border align/;
+    qw/alttag bgcolor fgcolor height width font transparent grid samples 
+    border align texwidth texfont plottype/;
 
 my $gnuplot_help_text = <<"ENDPLOTHELP";
 <p>
@@ -148,15 +151,22 @@ ENDPLOTHELP
 
 my %gnuplot_defaults = 
     (
+     alttag       => {
+	 default     => 'dynamically generated plot',
+	 test        => $words_test,
+	 description => 'brief description of the plot',
+      	 edit_type   => 'entry',
+	 size        => '40'
+	 },
      height       => {
-	 default     => 200,
+	 default     => 300,
 	 test        => $int_test,
 	 description => 'height of image (pixels)',
       	 edit_type   => 'entry',
 	 size        => '10'
 	 },
      width        => {
-	 default     => 200,
+	 default     => 400,
 	 test        => $int_test,
 	 description => 'width of image (pixels)',
 	 edit_type   => 'entry',
@@ -183,7 +193,7 @@ my %gnuplot_defaults =
 	 edit_type   => 'onoff'
 	 },
      grid         => {
-	 default     => 'off',
+	 default     => 'on',
 	 test        => $onoff_test, 
 	 description => 'Display grid',
 	 edit_type   => 'onoff'
@@ -201,13 +211,41 @@ my %gnuplot_defaults =
 	 edit_type   => 'choice',
 	 choices     => ['small','medium','large']
 	 },
+     samples         => {
+	 default     => '100',
+	 test        => $int_test,
+	 description => 'Number of samples for non-data plots',
+	 edit_type   => 'choice',
+	 choices     => ['100','200','500','1000','2000','5000']
+	 },
      align        => {
-	 default     => 'left',
+	 default     => 'center',
 	 test        => sub {$_[0]=~/^(left|right|center)$/},
 	 description => 'alignment for image in html',
 	 edit_type   => 'choice',
 	 choices     => ['left','right','center']
-	 } 
+	 },
+     texwidth     => {
+         default     => '93',
+         test        => $int_test,
+         description => 'Width of plot when printed (mm)',
+         edit_type   => 'entry',
+         size        => '5'
+         },
+     texfont     => {
+         default     => '22',
+         test        => $int_test,
+         description => 'Font size to use in TeX output (pts):',
+         edit_type   => 'choice',
+         choices     => [qw/10 12 14 16 18 20 22 24 26 28 30 32 34 36/],
+         },
+     plottype  => {
+	 default     => 'Cartesian',
+	 test        => sub {$_[0]=~/^(Polar|Cartesian)$/},
+	 description => 'Plot type:',
+	 edit_type   => 'choice',
+         choices     => ['Cartesian','Polar']
+         },
      );
 
 my %key_defaults = 
@@ -260,51 +298,60 @@ my %label_defaults =
      }
      );
 
-my @tic_edit_order = ('location','mirror','start','increment','end');
+my @tic_edit_order = ('location','mirror','start','increment','end',
+                      'minorfreq');
 my %tic_defaults =
     (
      location => {
 	 default => 'border', 
 	 test => sub {$_[0]=~/^(border|axis)$/},
-	 description => 'Location of tick marks',
+	 description => 'Location of major tic marks',
 	 edit_type   => 'choice',
 	 choices     => ['border','axis']
 	 },
      mirror => {
 	 default => 'on', 
 	 test => $onoff_test,
-	 description => 'mirror ticks on opposite axis?',
+	 description => 'mirror tics on opposite axis?',
 	 edit_type   => 'onoff'
 	 },
      start => {
 	 default => '-10.0',
 	 test => $real_test,
-	 description => 'Start ticks at',
+	 description => 'Start major tics at',
 	 edit_type   => 'entry',
 	 size        => '10'
 	 },
      increment => {
 	 default => '1.0',
 	 test => $real_test,
-	 description => 'Place a tick every',
+	 description => 'Place a major tic every',
 	 edit_type   => 'entry',
 	 size        => '10'
 	 },
      end => {
 	 default => ' 10.0',
 	 test => $real_test,
-	 description => 'Stop ticks at ',
+	 description => 'Stop major tics at ',
 	 edit_type   => 'entry',
 	 size        => '10'
 	 },
+     minorfreq => {
+	 default => '0',
+	 test => $int_test,
+	 description => 'Number of minor tics between major tic marks',
+	 edit_type   => 'entry',
+	 size        => '10'
+	 },         
      );
 
+my @axis_edit_order = ('color','xmin','xmax','ymin','ymax');
 my %axis_defaults = 
     (
      color   => {
 	 default => 'x000000', 
 	 test => $color_test,
-	 description => 'color of axes (x000000)',
+	 description => 'color of grid lines (x000000)',
 	 edit_type   => 'entry',
 	 size        => '10'
 	 },
@@ -354,7 +401,7 @@ required.  Unfortunately, you must make
 in the order gnuplot expects the data.
 </p><p>
 Specifying the data should usually be done with a perl variable or array, 
-such as \@Xdata and \@Ydata.  You may also specify numerical data seperated 
+such as \@Xdata and \@Ydata.  You may also specify numerical data separated 
 by commas.  Again, the order of the <b>data</b> tags is important.  The
 first tag will be the X data and the second will be the Y data.
 </p>
@@ -426,10 +473,10 @@ my %curve_defaults =
 my (%plot,%key,%axis,$title,$xlabel,$ylabel,@labels,@curves,%xtics,%ytics);
 
 sub start_gnuplot {
-    %plot    = ();      %key     = ();      %axis   = (); 
-    $title   = undef;   $xlabel  = undef;   $ylabel = undef;
-    $#labels = -1;      $#curves = -1;
-    %xtics    = ();      %ytics    = ();
+    undef(%plot);   undef(%key);    undef(%axis);
+    undef($title);  undef($xlabel); undef($ylabel);
+    undef(@labels); undef(@curves);
+    undef(%xtics);  undef(%ytics);
     #
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
@@ -465,7 +512,7 @@ sub end_gnuplot {
     my $randnumber;
     # need to call rand everytime start_script would evaluate, as the
     # safe space rand number generator and the global rand generator 
-    # are not seperate
+    # are not separate
     if ($target eq 'web' || $target eq 'tex' || $target eq 'grade' ||
 	$target eq 'answer') {
       $randnumber=int(rand(1000));
@@ -476,23 +523,23 @@ sub end_gnuplot {
 	## Determine filename
 	my $tmpdir = '/home/httpd/perl/tmp/';
 	my $filename = $ENV{'user.name'}.'_'.$ENV{'user.domain'}.
-	    '_'.time.'_'.$$.$randnumber.'_plot.data';
+	    '_'.time.'_'.$$.$randnumber.'_plot';
 	## Write the plot description to the file
 	&write_gnuplot_file($tmpdir,$filename,$target);
 	$filename = &Apache::lonnet::escape($filename);
 	## return image tag for the plot
 	if ($target eq 'web') {
 	    $result .= <<"ENDIMAGE";
-<img src    = "/cgi-bin/plot.gif?file=$filename&output=gif" 
-     width  = "$plot{'width'}" 
+<img src    = "/cgi-bin/plot.gif?file=$filename.data&output=gif" 
+     width  = "$plot{'width'}"
      height = "$plot{'height'}"
      align  = "$plot{'align'}"
-     alt    = "image should be /cgi-bin/plot.gif?$filename" />
+     alt    = "$plot{'alttag'}" />
 ENDIMAGE
         } elsif ($target eq 'tex') {
-	    &Apache::lonnet::ssi('cgi-bin/plot.gif?file=$filename'.
-				 '&output=eps');
-	    $result = "$filename.eps";
+	    #might be inside the safe space, register the URL for later
+	    &Apache::lonxml::register_ssi("/cgi-bin/plot.gif?file=$filename.data&output=eps");
+	    $result = '\graphicspath{{/home/httpd/perl/tmp/}}\includegraphics[width='.$plot{'texwidth'}.' mm]{'.&Apache::lonnet::unescape($filename).'.eps}';
 	}
     } elsif ($target eq 'edit') {
 	$result.=&Apache::edit::tag_end($target,$token);
@@ -599,7 +646,7 @@ sub start_title {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
     if ($target eq 'web' || $target eq 'tex') {
-	$title = &Apache::lonxml::get_all_text("/title",$$parser[-1]);
+	$title = &Apache::lonxml::get_all_text("/title",$parser);
 	$title=&Apache::run::evaluate($title,$safeeval,$$parstack[-1]);
 	$title =~ s/\n/ /g;
 	if (length($title) > $max_str_len) {
@@ -607,14 +654,13 @@ sub start_title {
 	}
     } elsif ($target eq 'edit') {
 	$result.=&Apache::edit::tag_start($target,$token,'Plot Title');
-	my $text=&Apache::lonxml::get_all_text("/title",$$parser[-1]);
+	my $text=&Apache::lonxml::get_all_text("/title",$parser);
 	$result.=&Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
-	my $text=$$parser[-1]->get_text("/title");
 	$result.=&Apache::edit::rebuild_tag($token);
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/title",$parser);
     }
     return $result;
 }
@@ -633,7 +679,7 @@ sub start_xlabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
     if ($target eq 'web' || $target eq 'tex') {
-	$xlabel = &Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
+	$xlabel = &Apache::lonxml::get_all_text("/xlabel",$parser);
 	$xlabel=&Apache::run::evaluate($xlabel,$safeeval,$$parstack[-1]);
 	$xlabel =~ s/\n/ /g;
 	if (length($xlabel) > $max_str_len) {
@@ -641,14 +687,13 @@ sub start_xlabel {
 	}
     } elsif ($target eq 'edit') {
 	$result.=&Apache::edit::tag_start($target,$token,'Plot Xlabel');
-	my $text=&Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
+	my $text=&Apache::lonxml::get_all_text("/xlabel",$parser);
 	$result.=&Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
-	my $text=$$parser[-1]->get_text("/xlabel");
 	$result.=&Apache::edit::rebuild_tag($token);	
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/xlabel",$parser);
     }
     return $result;
 }
@@ -668,7 +713,7 @@ sub start_ylabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
     if ($target eq 'web' || $target eq 'tex') {
-	$ylabel = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
+	$ylabel = &Apache::lonxml::get_all_text("/ylabel",$parser);
 	$ylabel = &Apache::run::evaluate($ylabel,$safeeval,$$parstack[-1]);
 	$ylabel =~ s/\n/ /g;
 	if (length($ylabel) > $max_str_len) {
@@ -676,14 +721,13 @@ sub start_ylabel {
 	}
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Plot Ylabel');
-	my $text = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
+	my $text = &Apache::lonxml::get_all_text("/ylabel",$parser);
 	$result .= &Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
-	my $text=$$parser[-1]->get_text("/ylabel");
 	$result.=&Apache::edit::rebuild_tag($token);
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/ylabel",$parser);
     }
     return $result;
 }
@@ -706,7 +750,7 @@ sub start_label {
 	my %label;
 	&get_attributes(\%label,\%label_defaults,$parstack,$safeeval,
 		    $tagstack->[-1]);
-	my $text = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
+	my $text = &Apache::lonxml::get_all_text("/label",$parser);
 	$text = &Apache::run::evaluate($text,$safeeval,$$parstack[-1]);
 	$text =~ s/\n/ /g;
 	$text = substr($text,0,$max_str_len) if (length($text) > $max_str_len);
@@ -715,16 +759,15 @@ sub start_label {
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Plot Label');
 	$result .= &edit_attributes($target,$token,\%label_defaults);
-	my $text = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
+	my $text = &Apache::lonxml::get_all_text("/label",$parser);
 	$result .= &Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
 	&Apache::edit::get_new_args
 	    ($token,$parstack,$safeeval,keys(%label_defaults));
 	$result.=&Apache::edit::rebuild_tag($token);
-	my $text=$$parser[-1]->get_text("/label");
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/label",$parser);
     }
     return $result;
 }
@@ -784,22 +827,25 @@ sub start_function {
     my $result='';
     if ($target eq 'web' || $target eq 'tex') {
 	if (exists($curves[-1]->{'data'})) {
-	    &Apache::lonxml::warning('Use of <function> precludes use of <data>.  The <data> will be omitted in favor of the <function> declaration.');
+	    &Apache::lonxml::warning
+                ('Use of the <b>curve function</b> tag precludes use of '.
+                 ' the <b>curve data</b> tag.  '.
+                 'The curve data tag will be omitted in favor of the '.
+                 'curve function declaration.');
 	    delete $curves[-1]->{'data'} ;
 	}
-        my $function = &Apache::lonxml::get_all_text("/function",$$parser[-1]);
+        my $function = &Apache::lonxml::get_all_text("/function",$parser);
 	$function = &Apache::run::evaluate($function,$safeeval,$$parstack[-1]);
 	$curves[-1]->{'function'} = $function; 
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Gnuplot compatible curve function');
-	my $text = &Apache::lonxml::get_all_text("/function",$$parser[-1]);
+	my $text = &Apache::lonxml::get_all_text("/function",$parser);
 	$result .= &Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
 	$result.=&Apache::edit::rebuild_tag($token);
-	my $text=$$parser[-1]->get_text("/function");
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/function",$parser);
     }
     return $result;
 }
@@ -820,12 +866,14 @@ sub start_data {
     my $result='';
     if ($target eq 'web' || $target eq 'tex') {
 	if (exists($curves[-1]->{'function'})) {
-	    &Apache::lonxml::warning('Use of <data> precludes use of .'.
-	    '<function>.  The <function> will be omitted in favor of '.
-            'the <data> declaration.');
+	    &Apache::lonxml::warning
+                ('Use of the <b>curve function</b> tag precludes use of '.
+                 ' the <b>curve data</b> tag.  '.
+                 'The curve function tag will be omitted in favor of the '.
+                 'curve data declaration.');
 	    delete($curves[-1]->{'function'});
 	}
-	my $datatext = &Apache::lonxml::get_all_text("/data",$$parser[-1]);
+	my $datatext = &Apache::lonxml::get_all_text("/data",$parser);
 	$datatext=&Apache::run::evaluate($datatext,$safeeval,$$parstack[-1]);
 	# Deal with cases where we're given an array...
 	if ($datatext =~ /^\@/) {
@@ -839,21 +887,21 @@ sub start_data {
 	my @data;
 	if ($datatext =~ /,/) { # comma deliminated
 	    @data = split /,/,$datatext;
-	} else { # Assume it's space seperated.
+	} else { # Assume it's space separated.
 	    @data = split / /,$datatext;
 	}
 	for (my $i=0;$i<=$#data;$i++) {
 	    # Check that it's non-empty
 	    if (! defined($data[$i])) {
 		&Apache::lonxml::warning(
-		    'undefined <data> value.  Replacing with '.
+		    'undefined curve data value.  Replacing with '.
 		    ' pi/e = 1.15572734979092');
 		$data[$i] = 1.15572734979092;
 	    }
 	    # Check that it's a number
 	    if (! &$real_test($data[$i]) & ! &$int_test($data[$i])) {
 		&Apache::lonxml::warning(
-		    'Bad <data> value of '.$data[$i].'  Replacing with '.
+		    'Bad curve data value of '.$data[$i].'  Replacing with '.
 		    ' pi/e = 1.15572734979092');
 		$data[$i] = 1.15572734979092;
 	    }
@@ -868,14 +916,13 @@ sub start_data {
 	push  @{$curves[-1]->{'data'}},\@data;
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Comma or space deliminated curve data');
-	my $text = &Apache::lonxml::get_all_text("/data",$$parser[-1]);
+	my $text = &Apache::lonxml::get_all_text("/data",$parser);
 	$result .= &Apache::edit::end_row().
 	    &Apache::edit::start_spanning_row().
-	    &Apache::edit::textfield('',$text,'',60);
+	    &Apache::edit::editline('',$text,'',60);
     } elsif ($target eq 'modified') {
 	$result.=&Apache::edit::rebuild_tag($token);
-	my $text=$$parser[-1]->get_text("/data");
-	$result.=&Apache::edit::modifiedfield($token);
+	$result.=&Apache::edit::modifiedfield("/data",$parser);
     }
     return $result;
 }
@@ -899,7 +946,8 @@ sub start_axis {
 			$tagstack->[-1]);
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Plot Axes');
-	$result .= &edit_attributes($target,$token,\%axis_defaults);
+	$result .= &edit_attributes($target,$token,\%axis_defaults,
+				    \@axis_edit_order);
     } elsif ($target eq 'modified') {
 	my $constructtag=&Apache::edit::get_new_args
 	    ($token,$parstack,$safeeval,keys(%axis_defaults));
@@ -940,8 +988,13 @@ sub set_defaults {
 sub get_attributes{
     my ($values,$defaults,$parstack,$safeeval,$tag) = @_;
     foreach my $attr (keys(%{$defaults})) {
-	$values->{$attr} = 
-	    &Apache::lonxml::get_param($attr,$parstack,$safeeval);
+	if ($attr eq 'texwidth' || $attr eq 'texfont') {
+	    $values->{$attr} = 
+		&Apache::lonxml::get_param($attr,$parstack,$safeeval,undef,1);
+	} else {
+	    $values->{$attr} = 
+		&Apache::lonxml::get_param($attr,$parstack,$safeeval);
+	}
 	if ($values->{$attr} eq '' | !defined($values->{$attr})) {
 	    $values->{$attr} = $defaults->{$attr}->{'default'};
 	    next;
@@ -962,6 +1015,7 @@ sub write_gnuplot_file {
     my ($tmpdir,$filename,$target)= @_;
     my $gnuplot_input = '';
     my $curve;
+    my $pt = $plot{'texfont'};
     # Collect all the colors
     my @Colors;
     push @Colors, $plot{'bgcolor'};
@@ -982,19 +1036,35 @@ sub write_gnuplot_file {
 	# set output
 	$gnuplot_input .= "set output\n";
     } elsif ($target eq 'tex') {
-	$gnuplot_input .= "set term postscript eps monochrome\n";
-	$gnuplot_input .= "set output \"$filename.eps\"\n";
+	$gnuplot_input .= "set term postscript eps monochrome solid \"Helvetica\" $pt \n";
+	$gnuplot_input .= "set output \"/home/httpd/perl/tmp/".
+	    &Apache::lonnet::unescape($filename).".eps\"\n";
+    }
+    # cartesian or polar?
+    if (lc($plot{'plottype'}) eq 'polar') {
+        $gnuplot_input .= 'set polar'.$/;
+    } else {
+        # Assume Cartesian
     }
     # grid
     $gnuplot_input .= 'set grid'.$/ if ($plot{'grid'} eq 'on');
     # border
     $gnuplot_input .= ($plot{'border'} eq 'on'?
 		       'set border'.$/           :
-		       'set noborder'.$/         );    # title, xlabel, ylabel
+		       'set noborder'.$/         );
+    # sampling rate for non-data curves
+    $gnuplot_input .= "set samples $plot{'samples'}\n";
+    # title, xlabel, ylabel
     # titles
-    $gnuplot_input .= "set title  \"$title\"\n"  if (defined($title)) ;
-    $gnuplot_input .= "set xlabel \"$xlabel\"\n" if (defined($xlabel));
-    $gnuplot_input .= "set ylabel \"$ylabel\"\n" if (defined($ylabel));
+    if ($target eq 'tex') {
+        $gnuplot_input .= "set title  \"$title\" font \"Helvetica,".$pt."pt\"\n"  if (defined($title)) ;
+        $gnuplot_input .= "set xlabel \"$xlabel\" font \"Helvetica,".$pt."pt\" \n" if (defined($xlabel));
+        $gnuplot_input .= "set ylabel \"$ylabel\" font \"Helvetica,".$pt."pt\"\n" if (defined($ylabel));
+    } else {
+        $gnuplot_input .= "set title  \"$title\"  \n"  if (defined($title)) ;
+        $gnuplot_input .= "set xlabel \"$xlabel\" \n" if (defined($xlabel));
+        $gnuplot_input .= "set ylabel \"$ylabel\" \n" if (defined($ylabel));
+    }
     # tics
     if (%xtics) {    
 	$gnuplot_input .= "set xtics $xtics{'location'} ";
@@ -1002,6 +1072,9 @@ sub write_gnuplot_file {
 	$gnuplot_input .= "$xtics{'start'}, ";
 	$gnuplot_input .= "$xtics{'increment'}, ";
 	$gnuplot_input .= "$xtics{'end'}\n";
+        if ($xtics{'minorfreq'} != 0) {
+            $gnuplot_input .= "set mxtics ".$xtics{'minorfreq'}."\n";
+        } 
     }
     if (%ytics) {    
 	$gnuplot_input .= "set ytics $ytics{'location'} ";
@@ -1009,6 +1082,9 @@ sub write_gnuplot_file {
 	$gnuplot_input .= "$ytics{'start'}, ";
 	$gnuplot_input .= "$ytics{'increment'}, ";
         $gnuplot_input .= "$ytics{'end'}\n";
+        if ($ytics{'minorfreq'} != 0) {
+            $gnuplot_input .= "set mytics ".$ytics{'minorfreq'}."\n";
+        } 
     }
     # axis
     if (%axis) {
@@ -1019,7 +1095,7 @@ sub write_gnuplot_file {
     if (%key) {
 	$gnuplot_input .= 'set key '.$key{'pos'}.' ';
 	if ($key{'title'} ne '') {
-	    $gnuplot_input .= 'title " '.$key{'title'}.'" ';
+	    $gnuplot_input .= 'title "'.$key{'title'}.'" ';
 	} 
 	$gnuplot_input .= ($key{'box'} eq 'on' ? 'box ' : 'nobox ').$/;
     } else {
@@ -1029,8 +1105,12 @@ sub write_gnuplot_file {
     my $label;
     foreach $label (@labels) {
 	$gnuplot_input .= 'set label "'.$label->{'text'}.'" at '.
-	    $label->{'xpos'}.','.$label->{'ypos'}.' '.$label->{'justify'}.$/ ;
+	    $label->{'xpos'}.','.$label->{'ypos'}.' '.$label->{'justify'}.' font "Helvetica,'.$pt.'pt"'.$/ ;
     }
+    if ($target eq 'tex') {
+        $gnuplot_input .="set size 1,".$plot{'height'}/$plot{'width'}*1.38;
+        $gnuplot_input .="\n";
+        }
     # curves
     $gnuplot_input .= 'plot ';
     for (my $i = 0;$i<=$#curves;$i++) {
@@ -1040,11 +1120,8 @@ sub write_gnuplot_file {
 	    $gnuplot_input.= 
 		$curve->{'function'}.' title "'.
 		$curve->{'name'}.'" with '.
-		$curve->{'linestyle'};
-#
-# gnuplot's term=gif driver does not handle linewidths :(
-# . ' linewidth '. $curve->{'linewidth'};
-#
+                $curve->{'linestyle'};
+            $gnuplot_input.= ' linewidth 4 ' if ($target eq 'tex');
             if (($curve->{'linestyle'} eq 'points')      ||
                 ($curve->{'linestyle'} eq 'linespoints') ||
                 ($curve->{'linestyle'} eq 'errorbars')   ||
@@ -1058,7 +1135,7 @@ sub write_gnuplot_file {
 	    # Store data values in $datatext
 	    my $datatext = '';
 	    #   get new filename
-	    my $datafilename = "$tmpdir/$filename.$i";
+	    my $datafilename = "$tmpdir/$filename.data.$i";
 	    my $fh=Apache::File->new(">$datafilename");
 	    # Compile data
 	    my @Data = @{$curve->{'data'}};
@@ -1077,6 +1154,7 @@ sub write_gnuplot_file {
 	    $gnuplot_input.= '"'.$datafilename.'" title "'.
 		$curve->{'name'}.'" with '.
 		$curve->{'linestyle'};
+            $gnuplot_input.= ' linewidth 4 ' if ($target eq 'tex');
             if (($curve->{'linestyle'} eq 'points')      ||
                 ($curve->{'linestyle'} eq 'linespoints') ||
                 ($curve->{'linestyle'} eq 'errorbars')   ||
@@ -1089,7 +1167,7 @@ sub write_gnuplot_file {
 	}
     }
     # Write the output to a file.
-    my $fh=Apache::File->new(">$tmpdir$filename");
+    my $fh=Apache::File->new(">$tmpdir$filename.data");
     print $fh $gnuplot_input;
     close($fh);
     # That's all folks.
@@ -1114,7 +1192,7 @@ sub check_inputs {
     my $curve;
     foreach $curve (@curves) {
 	if (!defined($curve->{'function'})&&!defined($curve->{'data'})){
-	    &Apache::lonxml::warning("One of the curves specified did not contain any <data> or <function> declarations\n");
+	    &Apache::lonxml::warning("One of the curves specified did not contain any curve data or curve function declarations\n");
 	    return '';
 	}
     }