Re: [Matplotlib-users] Any update to plot_surface? Problem to set it in log scale

2011/2/14 Gaël KANEKO <kan...@ho...>

>  Hi,
> I have some problems to plot a 3d plot_surface (and contour plot) in log
> scale (y and z or x,y and z).
> There is nothink in the help sections of thus plot to plot them in log
> scale (neither in thus plot code commentary).
> I tried to find a solution by myself (many try as "log=True",
> "xscale='log'", "scale='log'", or "set_xscale('log')"...) but it doesn't
> work.
> I tried to use "LogFormatter" (ticker) but i failed (maybe I am doing
> something wrong (I am a newbe) but i tried many things).
> I try to found a solution on forums and this mailing list and what i found
> nearest of my problem is this topic:
>
> http://stackoverflow.com/questions/3909794/plotting-mplot3d-axes3d-xyz-surface-plot-with-log-scale
> ‏ They said this problem had no solution. Is it true? have somebody solved
> this problem?
>
> An other solution is to plot log(Data) and change ticks with "set_ticks"
> (for exemple) but it seems to only work with 2D plot. I tried too :(
>
> To be unterstanding easier, this is an exemple of the code to plot in log
> scale:
>     import matplotlib.pyplot as plt#   (i am under '1.0.0')
>     import numpy as np
>
>     #Data
>     x = np.logspace(0, 4, 10)
>     y = np.logspace(0, 4, 10)
>     Z = np.arange(100).reshape((10,10))
>
>     #Min and Max for x,y and Z
>     minx=np.min(x)
>     maxx=np.max(x)
>     miny=np.min(y)
>     maxy=np.max(y)
>     minz=np.min(Z)
>     maxz=np.max(Z)
>
>     #figure
>     fig = plt.figure()
>     ax = fig.gca(projection='3d')
>
>
>     ax.plot_surface(X, Y, Z, rstride=8, cstride=8, alpha=0.3)
>     cset = ax.contour(X, Y, Z, zdir='z', offset=minz)
>     cset = ax.contour(X, Y, Z, zdir='x', offset=minx)
>     cset = ax.contour(X, Y, Z, zdir='y', offset=miny)
>
>     ax.set_xlabel("X")
>     ax.set_xlim3d(minx,maxx)
>     ax.set_ylabel("Y")
>     ax.set_ylim3d(miny,maxy)
>     ax.set_zlabel("Z")
>     ax.set_zlim3d(minz,maxz)
>     fig.savefig("plot00.png")
>
>
>
> Has someone got a solution?
> Thanks!
> Regards,
> Gaël
>
>
I can confirm (with a modified version of your script) that mplot3d does not
properly handle non-linear scaling.  While it is possible to set the axis
scale through a command like:

ax.w_xaxis.set_scale('log')

but the placement of the tickers are wrong and it fails because mplot3d does
some weird stuff with the ticker formatter rather than just letting the
formatter do its job.

I will look into this further to see if I can fix this.

Ben Root