From: Robert Konigsberg <konigsberg@google.com>
Date: Fri, 8 Oct 2010 14:03:57 +0000 (-0400)
Subject: y-axis scaling is automatic until a) user zooms in on the y-axis or b) a value range... 
X-Git-Tag: v1.0.0~613^2~12
X-Git-Url: https://adrianiainlam.tk/git/?a=commitdiff_plain;h=74f09e22ec074b0a1c2c8fc1e5f88e296121f7a6;p=dygraphs.git

y-axis scaling is automatic until a) user zooms in on the y-axis or b) a value range is defined on construction.
---

diff --git a/dygraph.js b/dygraph.js
index 2e7fa0f..f70bfa9 100644
--- a/dygraph.js
+++ b/dygraph.js
@@ -810,9 +810,14 @@ Dygraph.prototype.createDragInterface_ = function() {
       var maxDate = minDate + dateRange;
       self.dateWindow_ = [minDate, maxDate];
 
-      var maxValue = draggingValue + (dragEndY / self.height_) * valueRange;
-      var minValue = maxValue - valueRange;
-      self.valueWindow_ = [ minValue, maxValue ];
+      // if a y-axis as been defined then the y-axis scale is maintained.
+      // otherwise don't set a value window, thereby forcing automatic y-axis
+      // scaling.
+      if (self.valueWindow_) {
+        var maxValue = draggingValue + (dragEndY / self.height_) * valueRange;
+        var minValue = maxValue - valueRange;
+        self.valueWindow_ = [ minValue, maxValue ];
+      }
       self.drawGraph_(self.rawData_);
     }
   });