Reply To: Vector ops

Another question.

Say I have two vectors: [A B C D], [0 0 1 0] where the second is a logical vector indicating which element of the first vector to extract (probably computed from the vector itself). What is the best way to get a scalar C out?

I know I could do a pick(a,b) to get Nones or zeros like [None None C None], but how do I get the C out into a scalar? I know I could use a series of extract + picks (4 extract, 3 picks in this case), is there a better way?