Problem 645. Getting the indices from a vector

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</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>find the logical indices</w:t></w:r></w:hyperlink><w:r><w:t> of the elements of a vector that meet your criteria.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>This exercise is for finding the index of indices that meet your criteria. The difference is this:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[     vec = [11 22 33 44];\n  thresh = 25;\n      vi = (vec > thresh)\n\nvi =\n\n     0     0     1     1]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>What we are looking for now is how to get the values</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[   x =\n\n     3     4]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Because those are the indices where the binary comparison is true.</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>.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Given a vector, vec, return the indices where vec is greater than scalar, thresh.</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>"}]}

Solve

Solution Stats

4184 Solutions
2387 Solvers

Last Solution submitted on Sep 21, 2020

Last 200 Solutions

Problem Comments

3 Comments

3 Comments

goc3 on 18 Nov 2016

I added six more test cases.

Nguyen Huu Hung on 14 Sep 2019

hay

Kerem Kutan on 12 Jun 2020

kinda easy

Solution Comments

Solution 1936830

1 Comment

1 Comment

Umur Ulas Harman on 25 Jun 2020

function out = findIndices(vec, thresh)
[row,col]=find(vec>thresh);
out = col
end

Solution 1623474

2 Comments

2 Comments

Ahsan Naseer on 15 Sep 2018

my solution is incorrect.how would i get the exact solution?

Tavish Pattanayak on 8 May 2020

You can ask in the matlab center

Solution 382087

1 Comment

1 Comment

SJ Won on 2 Jul 2019

Can someone explain this solution to me?

Problem Recent Solvers2387

Problem Tags

Problem 645. Getting the indices from a vector

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers2387

Suggested Problems

More from this Author52

Problem Tags

Problem 645. Getting the indices from a vector

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers2387

Suggested Problems

More from this Author52

Problem Tags

Players