flooey/dygraphs — pull request #1 by flooey (2012-04-11 15:17:21+00:00)
Title: Fix bugs with stacked graph + missing points

This fixes two bugs that occur when stacked graphs and missing points interact. One is that if a point's previous point is NaN, then trying to subtract its value results in NaN (you can see this in the fourth graph at http://dygraphs.com/tests/stacked.html). The other is that if the point's value is null (happens when using connectSeparatedPoints), subtracting the previous point from it in a coercion to zero and thus a negative value for the missing point.