Problem 801. Construct an index vector from two input vectors in vectorized fashion

Created by Christopher

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745 Solutions
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Last Solution submitted on Feb 25, 2021

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Dirk Engel on 27 Jun 2012

Please do not check for the occurance of "for" in general, because "UniFORmOutput" has nothing to do with looping ;-)

Freddy on 27 Jun 2012

Your predefined function signature has only one parameter, altough two were submitted. Same problem without the "for" restriction: http://www.mathworks.com/matlabcentral/cody/problems/555-low-high-low-high-turn-around-create-a-subindices-vector

Pascal Wenger on 28 Feb 2017

This is an excellent problem.

Allen on 13 Oct 2017

I agree with Dirk. Change your regexp to check for instances of eval, for, and while that are not preceded or followed by additional letters.

N/A on 26 Feb 2018

b
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Payam Morsali on 17 Nov 2019

give me a hint, should we use a specific function here?

Rafael S.T. Vieira on 23 Jul 2020

Tip: replace UniformOutput with uni.

Rik on 25 Feb 2021 at 12:13

Actually arrayfun should also be outlawed, as that simply hides the loop at a performance cost. I haven't seen a vectorized solution yet, only recursions and implicit loops (and the usual cheat-submissions).

If you want a more robust cheat-detection you should have a separate test which runs as first test. That one should not call the submission to avoid it overwriting functions like fileread and assert.

Solution Comments

Solution 4528143

Solution 1575258

1 Comment

1 Comment

Jiahang Li on 4 Jul 2018

'uniformoutput' is innocent orz~~

Solution 287230

1 Comment

1 Comment

Evan on 22 Jul 2013

A separate test case that tests for functions that are against the rules would improve this problem. In this case, the "for" in "UniformOutput" was getting caught by the search. A separate test case would have made clear that the solution functions properly but contains an outlawed string.

Solution 104578

1 Comment

1 Comment

Jean-Marie Sainthillier on 12 Dec 2012

Wonderful !

Solution 104042

1 Comment

1 Comment

Jean-Marie Sainthillier on 12 Dec 2012

Why x3=[] in the test ?
Nice recursion !

Solution 104038

1 Comment

1 Comment

Jean-Marie Sainthillier on 12 Dec 2012

Each solution of Richard is a gem.

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Problem 801. Construct an index vector from two input vectors in vectorized fashion

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Problem 801. Construct an index vector from two input vectors in vectorized fashion

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Last 200 Solutions

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