Problem 451. Is this matrix orthogonal?

Created by Bruce Raine

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Last Solution submitted on Aug 06, 2022

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2 Comments

Alfonso Nieto-Castanon on 5 Mar 2012

perhaps you could these cases to avoid some non-general solutions... TEST1: x=sqrtm([2,1;1,1]); y_correct=false; TEST2: x=randn(3); y_correct=false;

Bruce Raine on 7 Mar 2012

Thanks for the suggestions. I have implemented both of the tests. Cheers.

Solution Comments

Solution 4363790

1 Comment

1 Comment

Yuvraj on 11 Jul 2022 at 21:37

The threshold 1.1 is hard coded. It would be better to use rounding off to nearest integer to ensure robustness. A false positive can occur where a non-orthogonal matrix with norm 1.05 is returned as orthogonal from this function

Solution 1266265

1 Comment

1 Comment

Andrew Dobrovolc on 11 Sep 2017

I believe the test cases are wrong, I could not prove that a matrix from randn(3) is orthogonal.

Solution 997317

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1 Comment

Adib on 27 Jul 2020

are you kidding ? :3 Great IQ !!

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Problem 451. Is this matrix orthogonal?

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Problem 451. Is this matrix orthogonal?

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