merge

diff --cc dygraph.js
index 1bfe873,effe10d..6fa21e8
--- 1/dygraph.js
--- 2/dygraph.js
+++ b/dygraph.js
@@@ -885,11 -854,10 +885,11 @@@ Dygraph.prototype.toDataYCoord = functi
    }
  
    var area = this.plotter_.area;
 -  var yRange = this.yAxisRange(axis);
 +  var yRange = this.yAxisRange(opt_axis);
 +
 +  var axis = opt_axis || 0;
  
-   if (!this.axes_[axis].logscale) {
 -  if (typeof(axis) == "undefined") axis = 0;
+   if (!this.attributes_.getForAxis("logscale", axis)) {
      return yRange[0] + (area.y + area.h - y) / area.h * (yRange[1] - yRange[0]);
    } else {
      // Computing the inverse of toDomCoord.