On 08/24/2015 10:23 AM, Sebastian Berg wrote:
Fabien, just to make sure you are aware. If you are overriding `__getitem__`, you should also implement `__setitem__`. NumPy does some magic if you do not. That will seem to make `__setitem__` work fine, but breaks down if you have advanced indexing involved (or if you return copies, though it spits warnings in that case).
Hi Sebastian, thanks for the info. I am writing a duck NetCDF4 Variable object, and therefore I am not trying to override Numpy arrays. I think that Stephan's function for xray is very useful. A possible improvement (probably at a certain performance cost) would be to be able to provide a shape instead of a number of dimensions. The output would then be slices with valid start and ends. Current behavior: In[9]: expanded_indexer(slice(None), 2) Out[9]: (slice(None, None, None), slice(None, None, None)) With shape: In[9]: expanded_indexer(slice(None), (3, 4)) Out[9]: (slice(0, 4, 1), slice(0, 5, 1)) But if nobody needed something like this before me, I think that I might have a design problem in my code (still quite new to python). Cheers and thanks, Fabien