How to extract a zero dimensional slice from a one dimensional array in numpy
Is there a way to slice a zero dimensional submatrix from a one dimensional array?
For example, if I have N-dimensional ndarray
arr
, it arr[0]
returns (N-1) -dimensional ndarray
.
However, if I have a 1-dimensional ndarray
x
, it x[0]
does not return a 0-dimensional ndarray, but rather a numpy.int64
, (if x
contains int64
s).
Minimal example:
def increment(zero_d_array):
zero_d_array[...] = zero_d_array + 1
counter = numpy.array(0) # a zero-dimensional array containing scalar 0
increment(counter) # success; counter is now 1
counters = numpy.zeros(3, dtype=int) # [0, 0, 0]
increment(counter[1]) # fails; counter[1] is a numpy.int64, not a 0-D array
I understand that the above will work with increment(counter[1:2])
, but only because it increment()
works with both 0-D and 1-D inputs. Not all features will be that flexible.
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