python - NumPy: 1D numpy array to slice a list -

how can extract elements of list corresponding indices contained in 1d numpy.ndarray?

here example:

list_data = list(range(1, 100)) arr_index = np.asarray([18, 55, 22]) arr_index.shape  list_data[arr_index]  # fails 

i want able retrieve elements of list_data corresponding arr_index.

you can use numpy.take -

import numpy np np.take(list_data,arr_index) 

sample run -

in [12]: list_data = list(range(1, 20))  in [13]: list_data out[13]: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]  in [14]: arr_index = np.asarray([3, 5, 12])  in [15]: np.take(list_data,arr_index) out[15]: array([ 4,  6, 13])