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

Created by Doug Hull

Solve Later

{"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","targetMode":"","relationshipId":"rId1","target":"/matlab/document.xml"},{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/output","targetMode":"","relationshipId":"rId2","target":"/matlab/output.xml"}],"parts":[{"partUri":"/matlab/document.xml","relationship":[],"contentType":"application/vnd.mathworks.matlab.code.document+xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\"><w:body><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>This is a basic MATLAB operation. It is for instructional purposes.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>---</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>You may already know how to get</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"http://www.mathworks.com/matlabcentral/cody/problems/640-do-a-binary-comparison-on-a-vector\"><w:r><w:t>logical indexes</w:t></w:r></w:hyperlink><w:r><w:t> from a vector, and to</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"http://www.mathworks.com/matlabcentral/cody/problems/645-getting-the-indices-from-a-vector\"><w:r><w:t>find the location</w:t></w:r></w:hyperlink><w:r><w:t> of elements in a vector.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>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:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[ [0 1 0\n 0 0 0]]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>You might want</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[row = 1\ncol = 2]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>or</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[ [0 1 1\n 1 0 0]\n\n row = [2\n 1\n 1]\n\n col = [1\n 2\n 3]]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Check out</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"http://www.mathworks.com/help/techdoc/ref/find.html\"><w:r><w:t>Find</w:t></w:r></w:hyperlink><w:r><w:t> to learn to do this.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>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.</w:t></w:r></w:p></w:body></w:document>"},{"partUri":"/matlab/output.xml","contentType":"text/xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?><embeddedOutputs><metaData><evaluationState>manual</evaluationState><layoutState>code</layoutState><outputStatus>ready</outputStatus></metaData><outputArray type=\"array\"/><regionArray type=\"array\"/></embeddedOutputs>"}]}

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.

Solve

Solution Stats

462 Solutions
246 Solvers

Last Solution submitted on Apr 16, 2021

Last 200 Solutions

Problem Recent Solvers246

Problem Tags

basics indexing ml101

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

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

Solution Stats

Last 200 Solutions

Problem Recent Solvers246

Suggested Problems

More from this Author52

Problem Tags

Community Treasure Hunt

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

Solution Stats

Last 200 Solutions

Problem Recent Solvers246

Suggested Problems

More from this Author52

Problem Tags

Community Treasure Hunt

Players