Dear Plots experts—sorry, another question. if I have 3-D data (not function), I can use surface for a nice interpolated plot. alas, it’s not been adapted to a contour plot. and it clearly needs some smoothing aspects, like loess, over x-y-z (not just over x-y). still, it would be very nice. does anyone know if such a thing exists?

using Plots
n=100; xr= 10*rand(n); yr= 10*rand(n); zr= Float64[ sin(xr[i])+cos(yr[i]) for i=1:n];
surface( xr, yr, zr ) ## does polygonal interpolation
contour( xr, yr, zr ) ## no such method

that depends on the backend, I think - gr should interpolate contours. By the way, a better way to get support is to go to the Plots gitter channel, or the plots-bridged Slack channel - discourse is more intended for persistent discussion.

looks too involved. the idea was to plot x,y,z data sets. Interpolations.jl seems to work happiest with regular grids. (only linear is supported without it.) With x and y not spaced equally, it’s not obvious enough to me how to work this well. plus, I think (but am not certain) that I have run into some bugs on Interpolations, either in the docs or in the package.

You can do it with GMT.jl. Unfortunately I forgot to port the contour module to the v0.5 version, but it’s now in master. With it you can do (contour the Matlab peaks function, also in GMT.jl)