[Numpy-discussion] NA/Missing Data Conference Call Summary

[Christopher Barker]

Christopher Jordan-Squire wrote:
> Here's a short-ish summary of the topics discussed in the conference 
> call this afternoon.

Thanks, this is great! And thanks to all who participated in the call.

> 3. Using IGNORE to signal a jagged array. e.g., [ [1, 2, IGNORE], 
> [IGNORE, 3, 4] ] should behave exactly the same as [ [1 , 2] , [3 , 4] 
> ].

whoooa!

I actually have been looking for, and thinking about "jagged arrays" a 
fair bit lately, so this is kind of exciting, but this looks like a "bad 
idea" to me. The above indicates that:

a = np.array( [ [1, 2, np.IGNORE],
                 [np.IGNORE, 3, 4] ]

a[:,1] would yield:

array([2, 4])

which seems really wrong -- you've tossed out the location information 
altogether.

( think it should be: array([2, 3])


I could see a jagged array being represented by IGNOREs all at the END 
of each row, but putting items in the middle, and shifting things to the 
left strikes me as a plain old bad idea (and a pain to implement)

-Chris



-- 
Christopher Barker, Ph.D.
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