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How to iterate over numpy array axes in array slicing?

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In short, I want to access a multidimensional array, starting with an entry, say a 4D array called "new_array".

new_array[0,1,2,3]

and getting as an output the sliced arrays

new_array[:,1,2,3],new_array[0,:,2,3],new_array[0,1,:,3],new_array[0,1,2,:] iterating over each axis in turn

I tried starting with "[0,1,2,3]" while replacing the "i-th" array with ":", but it's not a valid entry in python arrays.

It is possible to unroll it and do everything by hand, but this does not generalize over higher dimensional arrays. Is there a pythonic way of doing this?

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1 answer

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slice(None) will give you a value that's equivalent to a bare : in slice syntax. So you can write, for example,

for i in range(4):
    print(new_array[tuple(slice(None) if i == j else n for j, n in enumerate([0,1,2,3]))])
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Interesting - i did not know the "slice" function existed! In tests, this seems to function exactly ... (1 comment)

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