Don't do it. It's not good data visualization practice, and is explicitly and intentionally not supported in most grammar of graphics implementations. See, for one recent post I have handy: http://junkcharts.typepad.com/junk_charts/2014/02/a-message-worth-repeating.html
Two good alternatives are to stack/facet the graphs, one on top of each other, or to normalize the Y values so that they're proportions of their initial values. The latter's pretty common in financial plots, where Y=100 for X=min(X) for all series, so they start at the same point and then diverge. On Fri, Feb 28, 2014 at 10:20 AM, Sven Mesecke <sven.mese...@sveme.org>wrote: > I'd like to replicate the behavior of matlab's `plotyy` in Gadfly, i.e., > I'm trying to plot data with very different `y` axes but the same `x` axes > on the same plot, any idea of how to get this done? `layer` always seems to > use the same base `y` axis. > > Thanks for any pointers, > > Sven >
