Imagine that I have a python array like
array = [[2,3,4],[5,6,7],[8,9,10]]
And a list
list = [0,2,1]
I basically want a one liner to extract the indexed elements from the array given by the list
For example, with the given array and list:
result = [2,7,9]
My kneejerk option was
result = array[:, list]
But that did not work
I know that a for cycle should do it, I just want to know if there is some indexing that might do the trick
Something like this?
In [24]: a
Out[24]:
array([[ 2, 3, 4],
[ 5, 6, 7],
[ 8, 9, 10]])
In [25]: lis
Out[25]: [0, 2, 1]
In [26]: a[np.arange(len(a)), lis]
Out[26]: array([2, 7, 9])
Use enumerate to create row indices and unzip (zip(*...)) this collection to get the row indices (the range [0, len(list))) and the column indices (lis) :
a[zip(*enumerate(lis))]
