Problem 646. Getting the row and column location from a matrix

Created by Doug Hull

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This is a basic MATLAB operation. It is for instructional purposes.---You may already know how to get <a href="http://www.mathworks.com/matlabcentral/cody/problems/640-do-a-binary-comparison-on-a-vector">logical indexes</a> from a vector, and to <a href="http://www.mathworks.com/matlabcentral/cody/problems/645-getting-the-indices-from-a-vector">find the location</a> of elements in a vector.What if you are dealing with a matrix. Often you will want the row and column location of an element, or set of elements. For instance:<pre> [0 1 0
 0 0 0]</pre>You might want<pre class="language-matlab">row = 1
col = 2
</pre>or<pre> [0 1 1
 1 0 0]</pre><pre> row = [2
 1
 1]</pre><pre> col = [1
 2
 3]</pre>Check out <a href="http://www.mathworks.com/help/techdoc/ref/find.html">Find</a> to learn to do this.Given a matrix, M, return the column vectors that represent the row and column indices, r and c, where the given matrix, M is greater than the threshold value, thresh. R and C will be combined into matrix out.

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Problem 646. Getting the row and column location from a matrix

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