Re: [Matplotlib-users] Plot data from custom class

[Christopher B. <Chr...@no...>]

John Hunter wrote:
> But numpy.asarray, which is what mpl uses to convert inputs to
> arrays,

The whole idea of asarray, is that it should be able to convert properly
defined objects without even copying the data.

> my own custom class which contains data members, methods and an array
> of data (underlying C array)

This sounds like EXACTLY the type of object that the array interface is 
supposed to support. So what you need to do is give your object an array 
interface:

http://numpy.scipy.org/array_interface.shtml

once you've done that, asarray() should "just work" and therefore all of 
MPL should just work.

However, I would post a question about this to the numpy list -- there 
is an effort at the moment to have an n-d buffer protocol defined for 
Python 3.0.

http://projects.scipy.org/mailman/listinfo/numpy-discussion

I'm not sure at this point whether you'd be best off implementing the 
above interface or the new buffer protocol that's being discussed:

http://projects.scipy.org/scipy/numpy/browser/trunk/numpy/doc/pep_buffer.txt

The numpy folks will be able to help.

By the way, this is a good example why the above PEP is a good idea!

-Chris

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Christopher Barker, Ph.D.
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Chr...@no...