Problem 105. How to find the position of an element in a vector without using the find function

Created by Chelsea

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>Write a function posX=findPosition(x,y) where x is a vector and y is the number that you are searching for.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Examples:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[ findPosition([1 3 5 4 2], 2)\n posX is 5\n\n findPosition([1 5 8 6 7 6 0], 8)\n posX is 3]]></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

4921 Solutions
2453 Solvers

Last Solution submitted on Dec 02, 2020

Last 200 Solutions

Problem Comments

8 Comments

8 Comments

Show 5 older comments

Will on 26 Jan 2012

not set up right - only one input provided

the cyclist on 26 Jan 2012

Ditto Will's comment

Nickolas Cheilakos on 26 Jan 2012

Please corect it or remove it.

Ned Gulley on 26 Jan 2012

Acting as an Admin, I tried to clean up the problem. I am rescoring, but naturally some of the "correct" answers will now fail.

David Young on 1 Feb 2012

Lots of "solutions" use the find function. I don't get it - what's the point of doing the problem if you ignore the key instruction?

Freddy on 15 Mar 2012

May you please add this (or something similar) to the test suite:

% Test for find usage
fid = fopen(which('test'), 'r');
c = onCleanup(@()fclose(fid));
tline = fgetl(fid);
while ischar(tline),
if strfind(tline,'find'),
error('Don''t use find');
end
tline = fgetl(fid);
end

This should work fine after you've renamed your function.

Mineralter on 26 Jun 2013

there should be more test suite. such as x =[1 2 3;4 5 6;7 8 9];y =5;then the output is [2,2]; x = [1 2 2 3]; y =2;then the output is [2;2];

Ayanle Aden on 17 Jun 2018

The test suite needs to be very restrictive here, the amount of trivial solutions is alarming. Yan

Solution Comments

Solution 1017461

1 Comment

1 Comment

David Verrelli on 3 Sep 2018

This user (mohamed elbesealy) appears to have gamed the system, with fraudulent "likes" of this unremarkable solution submitted by 'sock-puppet' accounts. —DIV

Solution 878428