message: Always use the provided labels in asy graphs if there is more than on data set.
diff: @@ -241,8 +241,9 @@ for(int n = 0; n < Nx.length; ++n)
  graphpen = darkgreen;
  string legend = myleg ? legends[n] : texify(testlist[n]);
  marker mark = marker(scale(0.5mm) * unitcircle, Draw(graphpen + solid));
  - // Multi-axis graphs: set legend to appropriate y-axis.
  - if(secondaryaxis != "")
  +
  + // Multi-axis graphs: if only one data set, set legend to appropriate y-axis.
  + if(testlist.length == 1 && secondaryaxis != "")
  legend = "time";
  // We need to plot pairs for the error bars.
  