Re: [Numpy-discussion] question about a data structure

29/07/09 @ 14:54 (-0700), thus spake Christopher Barker:

Robert Kern wrote:

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2009/7/29 Ernest Adrogué :

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Now, I need to be able to differentiate between 0 and 'no data'.

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Is it possible to do this with the standard array class?

Not really. Use masked arrays. Or use a dictionary.

masked arrays are made precisely for this. However, if you can use floating point numbers, you could use NaN for the no data entries.

Thanks for the advice. Actually, I think I'll use a combination of a dictionary and a masked array. I have been playing around a bit and it doesn't seem too difficult to do. It works by adding an extra property to the array objects, which is a tuple with the "keys", and then use the __getitem__ and __setitem__ methods to translate the keys into numbers. This way it's possible to use strings in subscripts and slices. Ernest