add clear function to hplot

diff --git a/tools/HPlot.pm b/tools/HPlot.pm
index 362abccc9264311775b0eaaada4ea97f01d985ce..b559cdf0e7201fb164281a34323be179a1cc5cd6 100755 (executable)
--- a/tools/HPlot.pm
+++ b/tools/HPlot.pm
@@ -327,6 +327,14 @@ sub PlotDraw {
     }
   }
 
+sub PlotClear {
+  my ($name) = @_;
+  for(my $j=0; $j<$p->{$name}->{curves}; $j++) {
+    for(my $i=0; $i< $p->{$name}->{entries}; $i++) {
+      $p->{$name}->{value}->[$j]->[$i] = undef;
+      }
+    }
+  }
 
 sub PlotAdd {
   my($name,$value,$curve) = @_;