I explicitly ignore all lines that have '-' values

These may come from vnl-filter -p "dx=diff(x)" ... output. For instance, this
plot is broken before this patch:

  (echo '# x'; seq 5) | vnl-filter --noskipempty -p 'd=diff(x)' \
  | feedgnuplot --lines

Changes

@@ -1,3 +1,24 @@
+feedgnuplot (1.62)
+
+  * I explicitly ignore all lines that have '-' values
+    These may come from vnl-filter -p "dx=diff(x)" ... output. For instance, this
+    plot is broken before this patch:
+
+      (echo '# x'; seq 5) | vnl-filter --noskipempty -p 'd=diff(x)' \
+      | feedgnuplot --lines
+
+ -- Dima Kogan <dkogan@debian.org>  Sat, 27 Jan 2024 17:01:18 -0800
+
+feedgnuplot (1.61)
+
+  * #! line uses /usr/bin/env to work with nonstandard installations
+  * Added --cblabel to label the color bar
+  * Added --cbmin, --cbmax
+  * --zmin,--zmax,--zlabel are always sent, if requested
+  * Plotting with no STDIN data works
+
+ -- Dima Kogan <dkogan@debian.org>  Fri, 04 Mar 2022 14:45:36 -0800
+
 feedgnuplot (1.60)
 
   * Test suite fix: we have the right number of tests

bin/feedgnuplot

@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 package feedgnuplot; # for the metacpan indexer
 
@@ -16,7 +16,7 @@ use Pod::Usage;
 use Time::Piece;
 
 # Makefile.PL assumes this is in ''
-my $VERSION = '1.60';
+my $VERSION = '1.62';
 
 my %options;
 interpretCommandline();
@@ -115,11 +115,12 @@ sub interpretCommandline
 
              '3d!', 'colormap!', 'lines!', 'points!', 'circles',
              'legend=s{2}', 'autolegend!',
-             'xlabel=s', 'x2label=s', 'ylabel=s', 'y2label=s', 'zlabel=s',
+             'xlabel=s', 'x2label=s', 'ylabel=s', 'y2label=s', 'zlabel=s', 'cblabel=s',
              'title=s', 'xlen=f',
              'xmin=s', 'xmax=s', 'x2min=s', 'x2max=s',
              'ymin=f', 'ymax=f', 'y2min=f', 'y2max=f',
              'zmin=f', 'zmax=f',
+             'cbmin=f', 'cbmax=f',
              'x2=s@', 'y2=s@', 'x1y2=s@', 'x2y1=s@', 'x2y2=s@',
              'style=s{2}', 'curvestyle=s{2}', 'curvestyleall=s', 'styleall=s', 'with=s',
              'extracmds=s@', 'cmds=s@',
@@ -422,15 +423,6 @@ sub interpretCommandline
       exit -1;
     }
 
-    if(!$options{colormap})
-    {
-      if ( defined $options{zmin} || defined $options{zmax} || defined $options{zlabel} )
-      {
-        print STDERR "--zmin/zmax/zlabel only makes sense with --3d or --colormap\n";
-        exit -1;
-      }
-    }
-
     if ( defined $options{square_xy} )
     {
       print STDERR "--square_xy only makes sense with --3d\n";
@@ -788,6 +780,12 @@ sub mainThread
       $options{curvestyleall} = "with circles $options{curvestyleall}";
     }
 
+    # Required to ignore all lines that have '-' values, such as may come from
+    # vnl-filter -p "dx=diff(x)" ... output. For instance, this plot is broken
+    # without this extra line:
+    #   (echo '# x'; seq 5)  | vnl-filter --noskipempty -p 'd=diff(x)' | ./feedgnuplot --lines
+    print PIPE "set datafile missing \"-\"\n";
+
     print PIPE "set style data $style\n" if $style;
     print PIPE "set grid\n";
 
@@ -796,6 +794,7 @@ sub mainThread
     print(PIPE "set ylabel  \"$options{ylabel }\"\n") if defined $options{ylabel};
     print(PIPE "set y2label \"$options{y2label}\"\n") if defined $options{y2label};
     print(PIPE "set zlabel  \"$options{zlabel }\"\n") if defined $options{zlabel};
+    print(PIPE "set cblabel \"$options{cblabel}\"\n") if defined $options{cblabel};
     print(PIPE "set title   \"$options{title  }\"\n") if defined $options{title};
 
     if($options{square})
@@ -888,7 +887,15 @@ sub mainThread
     sendRangeCommand( "xrange",  $options{xmin}, $options{xmax} );
     sendRangeCommand( "yrange",  $options{ymin}, $options{ymax} );
     sendRangeCommand( "zrange",  $options{zmin}, $options{zmax} );
-    sendRangeCommand( "cbrange", $options{zmin}, $options{zmax} ) if($options{colormap});
+    if($options{colormap})
+    {
+        # legacy behavior. Nobody should really be using --colormap
+        sendRangeCommand( "cbrange", $options{zmin}, $options{zmax} );
+    }
+    else
+    {
+        sendRangeCommand( "cbrange", $options{cbmin},$options{cbmax});
+    }
 
     # add the extra global options
     print(PIPE "$_\n")       foreach (@{$options{extracmds}});
@@ -1176,9 +1183,10 @@ sub plotStoredData
   my @nonemptyCurves = grep { $_->{datastring} } @curves;
   my @extraopts = map {$_->{options}} @nonemptyCurves;
 
-  my $body = join('', map { "$_," } @{$options{equation}});
+  my @components = (@{$options{equation}},
-  $body   .= join(', ' , map({ "'-' $_" } @extraopts) );
+                    map({ "'-' $_" } @extraopts),
-  $body   .= join('', map { ",$_" } @{$options{'equation-above'}});
+                    @{$options{'equation-above'}});
+  my $body = join(',', @components);
 
   if($options{'3d'}) { print PIPE "splot $body\n"; }
   else               { print PIPE  "plot $body\n"; }
@@ -1924,9 +1932,16 @@ Interpret the X data as a time/date, parsed with the given format
 
 C<--colormap>
 
-Show a colormapped xy plot. Requires extra data for the color. zmin/zmax can be
+This is a legacy option used to who a colormapped xy plot. It does:
-used to set the extents of the colors. Automatically sets the
+
-C<--rangesize>/C<--tuplesize>.
+- Adds C<palette> to C<--curvestyleall>
+
+- Adds 1 to the default C<--tuplesize> (if C<--tuplesizeall> is not given
+
+- Uses C<--zmin>, C<--zmax> to set the colorbar range
+
+It's clearer to set the relevant options explicitly, but C<--colormap> still
+exists for compatibility
 
 =item
 
@@ -2003,10 +2018,11 @@ instance C<--set 'xrange [20:10]'> to set the given inverted bounds.
 
 =item
 
-C<--xlabel/x2label/ylabel/y2label/zlabel xxx>
+C<--xlabel/x2label/ylabel/y2label/zlabel/cblabel xxx>
 
 Label the given axis. The x2/y2-axis labels do not apply to 3d plots while the
-z-axis label applies I<only> to 3d plots.
+z-axis label applies I<only> to 3d plots. The "cblabel" applies to the colorbar,
+if there is one.
 
 =item
 

completions/bash/feedgnuplot

@@ -66,6 +66,7 @@ complete -W               \
     --zlabel              \
     --zmax                \
     --zmin                \
+    --cblabel             \
     --xticlabels          \
     --using               \
     --usingall            \

completions/zsh/_feedgnuplot

@@ -14,6 +14,7 @@ _arguments -S
     '--ylabel:Y-axis label:'                                                      \
     '--y2label:Y2-axis label:'                                                    \
     '--zlabel:Z-axis label:'                                                      \
+    '--cblabel:Colorbar label:'                                                      \
     '--title:Plot title:'                                                         \
     '--autolegend[Label each plot with its data ID]'                              \
     '(--3d)--xlen[the size of the x-window to plot]:window size:'                 \