add mayavi

[grlee77]

I have updated the mayavi recipe from #285, with minimal changes to update it to the latest version (4.5.0).

One question I came across was how to handle installing the examples (or whether to do it?). The build scripts had lines to move the examples folder to a $EXAMPLES location, but this variable doesn't seem to be defined so I have commented that out for now. (The mayavi repo has an examples subfolder that itself contains 2 directories containing various mayavi and tvtk examples).

pinging @msarahan as the original author of this recipe.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I wanted to let you know that I linted all conda-recipes in your PR (recipes/mayavi) and found some lint.

Here's what I've got...

For recipes/mayavi:

• The recipe must have a build/number section.

[grlee77]

Hmm... looks like maybe the current VTK on conda-forge is incompatible. I see the following in the
logs:

    from vtkRenderingOpenGLPython import *
ImportError: No module named vtkRenderingOpenGLPython

I only tested this on successfully on linux prior to uploading, but in that case I was using a locally built VTK recipe rather than the conda-forge one. I think the only difference in my local VTK recipe is that I am using the new default OpenGL2 backend while the conda-forge recipe forces the older OpenGL backend.

[grlee77]

Should have mentioned that the error above was on circleci (Python 3.5).

Python 3.5 passed on windows, but 2.7 and 3.4 build but then fail during testing with

ImportError: No module named 'tvtk'
TESTS FAILED: mayavi-4.5.0-py34_0

The fact that the windows py3.5 build passes despite the older OpenGL backend makes me think maybe that is not the culprit for the CircleCI build failure.

[patricksnape]

I think this version of Mayavi requires VTK > 6, just as a note.

[dfroger]

http://docs.enthought.com/mayavi/mayavi/installation.html has a note:

As new versions of VTK become available, Mayavi is continuously updated to support 
the latest releases. If your VTK version is newer than 6.2.0, please check the Changelog
for the current status of Mayavi. 

Changelog does not mention that Mayavi supports VTK versions > 6.2.0.

I propose to have conda packages for VTK 6.2.0, for Python 2.7 and 3.5, and use it for Mayavi 4.5.0

[dfroger]

Ah, I didn't kwon that....

http://www.vtk.org/Wiki/VTK/Python_Wrapping_FAQ#Python_Versions:

Versions of VTK prior to 7.0 will only work with Python 2.

[Cadair]

I would love to see this in conda forge, it's been on my todo list for months.

[asmeurer]

What's the status of this? I would love to see Mayavi in conda-forge.

[dfroger]

this can be close, as #2215 is merged. Other PR coming for windows and osx...