Question
I need to find unique rows in a numpy.array.
For example:
>>> a # I have
array([[1, 1, 1, 0, 0, 0],
[0, 1, 1, 1, 0, 0],
[0, 1, 1, 1, 0, 0],
[1, 1, 1, 0, 0, 0],
[1, 1, 1, 1, 1, 0]])
>>> new_a # I want to get to
array([[1, 1, 1, 0, 0, 0],
[0, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 1, 0]])
I know that i can create a set and loop over the array, but I am looking for
an efficient pure numpy solution. I believe that there is a way to set data
type to void and then I could just use numpy.unique, but I couldn't figure
out how to make it work.
Answer
As of NumPy 1.13, one can simply choose the axis for selection of unique
values in any N-dim array. To get unique rows, use
np.unique
as follows:
unique_rows = np.unique(original_array, axis=0)
