Clear graph when numAxes goes from 1 -> 2 in updateOptions

diff --git a/src/dygraph.js b/src/dygraph.js
index 1de4485..4676a2e 100644 (file)
--- a/src/dygraph.js
+++ b/src/dygraph.js
@@ -3103,6 +3103,7 @@ Dygraph.prototype.updateOptions = function(input_attrs, block_redraw) {
   // copyUserAttrs_ drops the "file" parameter as a convenience to us.
   var file = input_attrs.file;
   var attrs = Dygraph.copyUserAttrs_(input_attrs);
+  var prevNumAxes = this.attributes_.numAxes();
 
   // TODO(danvk): this is a mess. Move these options into attr_.
   if ('rollPeriod' in attrs) {
@@ -3126,6 +3127,7 @@ Dygraph.prototype.updateOptions = function(input_attrs, block_redraw) {
 
   this.attributes_.reparseSeries();
 
+  if (prevNumAxes < this.attributes_.numAxes()) this.plotter_.clear();
   if (file) {
     // This event indicates that the data is about to change, but hasn't yet.
     // TODO(danvk): support cancellation of the update via this event.