get specific elements from matrix

2012 5 2
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Hello,
From an arbitrary matrix I want to extract n elements when I have 2 arrays of lenth n, one containing the row indices and 1 containing the column indices of the desired elements.
For effeciency I would like to avoid a for loop. Is this possible?
Thanks!

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Richard
Richard 2012-5-2
could you provide an example?
Erik de Boer
Erik de Boer 2012-5-2
Sure
Say I have a matrix A =
[3 6 2
5 1 3
4 7 8]
Row vector R = [1 2 3] and column vector C = [3 1 1]
Then I want to etract the elements [1,3],[2,1],[3,1] and arrive at
ans = [2 5 4]
Walter Robertson's aswer does exactly that. Thanks!

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