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POMatrix Transform
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copied!<p>I am working on a project in which I need to transform the result matrix to a simpler matrix. More specifically, for each column in matrix, I want to find the maximum value in row and change it to 1, and the rest of the values will be change to 0. I am not sure how to search this question so I decide to post it here.</p> <p>For example, I have a matrix X:</p> <pre><code>X = [2 8 4; 7 3 9;1 2 3]; X = 2 8 4 7 3 9 1 2 3 </code></pre> <p>and I want to transform this matrix to </p> <pre><code>X' = 0 1 0 1 0 1 0 0 0 </code></pre> <p>I only know how to use for loop to return the maximum value from each row, but I am not sure how to return the position in matrix of that value and convert the rest to zero.</p> <p>Here is my idea</p> <ol> <li>Create a new same dimension zero matrix first</li> <li>Find the maximum value in row </li> <li>Find the position of the maximum value</li> <li>Assign the value 1 into new matrix at same position</li> <li>Repeat 2 and 3 by for loop</li> </ol> <p>I am new to Matlab, hope you can help.</p> <p>Here is one of the result of my program</p> <pre><code> 2.0680 17.7410 0.8992 -3.0221 3.6093 7.3443 6.7442 0.9874 -0.9095 -3.3220 -1.4857 -0.0023 -1.1753 -16.7906 0.3672 3.7697 -1.6856 -6.0929 -2.8614 0.5054 1.0794 3.8352 1.9894 0.1686 -0.4584 -0.3923 -1.2525 -0.4761 </code></pre> <p>And I want this matrix transform to </p> <pre><code>0 1 0 0 1 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 </code></pre> <p>So I think the reason why max() not work is becuase I have negative value inside the matrix</p> <p>Other example which not wotk with max() Columns 1 through 5</p> <pre><code> 0.3816 23.2243 19.6435 23.2243 -3.1993 3.8674 8.0762 6.0563 8.0762 1.8475 -0.4442 -4.0758 -3.4244 -4.0758 0.2073 0.7639 -22.3618 -19.1365 -22.3618 3.9892 -1.8128 -6.4602 -5.1011 -6.4602 -0.4536 0.2954 3.5886 3.1529 3.5886 -0.1403 -0.3723 0.8057 0.6607 0.8057 -0.5173 </code></pre> <p>Columns 5 through 10</p> <pre><code> 1.4814 19.6435 3.3100 23.2243 1.4814 7.0255 6.0563 6.5251 8.0762 7.0255 -1.1483 -3.4244 -1.1448 -4.0758 -1.1483 -0.7784 -19.1365 -2.3904 -22.3618 -0.7784 -3.8880 -5.1011 -3.7437 -6.4602 -3.8880 1.0289 3.1529 0.7994 3.5886 1.0289 -0.3723 0.8057 0.6607 0.8057 -0.5173 </code></pre> <p>Columns 11 through 15</p> <pre><code> 21.3957 19.6435 1.4814 0.3816 -3.1993 8.5765 6.0563 7.0255 3.8674 1.8475 -4.0793 -3.4244 -1.1483 -0.4442 0.2073 -20.7498 -19.1365 -0.7784 0.7639 3.9892 -6.6046 -5.1011 -3.8880 -1.8128 -0.4536 3.8181 3.1529 1.0289 0.2954 -0.1403 0.4994 0.6607 -0.5829 -0.3723 -0.5173 </code></pre> <p>Columns 16 through 20</p> <pre><code> -1.7736 9.5635 20.0251 1.8072 0.3816 1.6114 7.0884 9.9237 3.6313 3.8674 -0.0058 -2.3835 -3.8685 -0.6572 -0.4442 2.1941 -8.7540 -18.3726 -1.0312 0.7639 -0.5815 -4.5430 -6.9138 -1.9407 -1.8128 0.1232 2.4470 3.4483 0.5589 0.2954 -0.3588 -0.2377 0.2884 -0.2138 -0.3723 </code></pre> <p>The correct answer is use bsxfun(@eq, output, max(output))</p>

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