Re: [Matplotlib-users] Two questions

[Todd M. <jm...@st...>]

On Thu, 2004-04-22 at 08:48, John Hunter wrote:
> >>>>> "Kenneth" == Kenneth McDonald <kmm...@wi...> writes:
> 
>     Kenneth> 1) (Simple) Is there a defined behavior for matplotlib
>     Kenneth> when it attempts to graph data containing NaN values?
>     Kenneth> (OK, I admit-- it's really, really late, and I have tried
>     Kenneth> it to see what happens.  But even that wouldn't tell me
>     Kenneth> if that was the _defined_ behavior :-))
> 
> No, it's not defined.  I don't know that NaN is defined across
> platforms in python.  See my recent question on comp.lang.python
> 
> http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=mailman.141.1080681106.20120.python-list%40python.org&rnum=3&prev=/groups%3Fq%3Dtest%2Bnan%2Bgroup%253A*python*%26ie%3DUTF-8%26oe%3DUTF-8%26hl%3Den%26btnG%3DGoogle%2BSearch
> 
> Perhaps Todd or Perry can comment on what the status of NaN vis-a-vis
> Numeric and numarray.  

I'm not aware of any functionality in Numeric for dealing with IEEE
special values.  (Looking in the Numeric manual suggests that problems
with these values lead to the development of the Masked Array capability
as an alternative.)  Lack of support for IEEE special values in Numeric
makes it difficult to provide a unified approach in matplotlib.

numarray has a module (ieeespecial) for dealing with different IEEE
special values, including NaN.  In numarray.ieeespecial are functions
for identifying the locations of and setting IEEE special values to some
other value.  My thought was that you could use these functions in your
own code to define whatever behavior you want.  This is perhaps more
work than is convenient but has the advantage that you can do it now
yourself.  

Regards,
Todd

-- 
Todd Miller <jm...@st...>