Problem 7. Column Removal

Created by Cody Team

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Last Solution submitted on Jun 02, 2023

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21 Comments

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Jon on 13 Nov 2013

All solutions with score 11 or 12 use the regexp cheat.

Len on 11 Sep 2014

Is there somewhere to go to receive advice on how to improve your code?

Salil Goel on 17 Mar 2015

i can't think of a better solution having size less than 19!

Nicholas Hind on 21 Apr 2015

why isn't B = (A(:,n)=[]); working? thanks

Jyotsna mallela on 8 Jun 2015

How to improvise this code?

Noriko Hounoki on 7 Dec 2016

It's very MATLAB!

Raynald Belmont on 18 Dec 2016

this was actually not that difficult :)

Rasheed Abid on 31 Jan 2017

a good way to learn

David Verrelli on 19 Mar 2017

There should be a single-column input matrix in the test suite.

Mohsen Khodadadi on 29 Mar 2017

This was fun! Not difficult, but kind of challenging!

cqut on 22 Dec 2017

A(n,:)=[]; B = A; it works,but I'm wrong,who tell me the reason?

Varun Garg on 7 May 2018

Better test cases could be provided for edge cases.

Ashish Khulbey on 26 Jul 2019

Great problem.
Lets you dug deep into the documentation for an awesome solution.
This link might help : https://in.mathworks.com/help/matlab/math/removing-rows-or-columns-from-a-matrix.html

Trinh Tran on 13 Oct 2019

Good problem

Jyothsna Chintala on 21 Apr 2020

good

Tamás Utasi on 5 May 2020

Good one

Faruk Kaplan on 4 Jun 2020

Why this is not working?
B = A ( : , ~=n)
I know logic operator needs something~=n but I cannot decide how to correct it? Also, I can write if statement in a for loop but its size is huge.

源樹上林 on 13 Aug 2020

good

Shivi Shrivastava on 26 May 2021

function B = column_removal(A,n)
A(:,n) = [];
B = A;
end

Can someone please tell me what is wrong with this code?

Dyuman Joshi on 26 May 2021

@Shivi, it does work.

Eleanor on 14 Jul 2022

The tests don't check the cases for n=1 and n=num_cols(A).

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Problem 7. Column Removal

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