Problem 640. Getting logical indexes
This is a basic MATLAB operation. It is for instructional purposes.
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Logical indexing works like this.
thresh = 4; vec = [1 2 3 4 5 6 7 8];
vi = (vec > thresh)
vi =
0 0 0 0 1 1 1 1
Once you have this TRUE FALSE vector (I call it vi: Valid Indices)
It can be used to get the values out:
big = vec(vi)
big =
5 6 7 8
Given a vector, vec, and a value, v, return a binary vector that represents the indices where vector, vec, is equal to scalar, v.
Note, this works just as well with scalars and matrices.
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To get the indices where this comparison is true, see this Cody problem.
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