I have an array of values for example x = array([[[-0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. , 0. , 0. , 0. ], [ 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. , 0. , 0. ], [ 0. , 0. , 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. ], [ 0. , 0. , 0. , 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487]], [[-0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. , 0. , 0. , 0. ], [ 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. , 0. , 0. ], [ 0. , 0. , 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487, 0. ], [ 0. , 0. , 0. , 0. , -0.78867513, -0.21132487, 0. , 0.78867513, 0.21132487]]]) I want in use advanced indexing to pull out the nonzero values. I know the indices of the nonzero values so idx = array([[4, 3, 1, 0], [5, 4, 2, 1], [7, 6, 4, 3], [8, 7, 5, 4]]) The desired result would be something like x[idx] = array([[[-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487]], [[-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487], [-0.78867513, -0.21132487, 0.78867513, 0.21132487]]]) The actual x array is much larger along the first dimension, but the nonzero structure is always indicated by idx so I need it to broadcast along the first dimension. Is this possible? EDIT: To be clear x along the first dimension contains a nested list of 4 x 9 array. idx then has the nonzero entries row-for-row. Notice in the first row of the both 4 x 9 nested arrays in x that the 4 3 1 0 entries are nonzero. Continue reading...
