delete element from vector

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Majid Al-Sirafi on 24 Sep 2012
Commented: Joel Bay on 28 Jun 2019
Hi everyone
how can I delete element from vector .... for example
a=[1,2,3,4,5]
how can I delete 3 from above vector to be
a=[1,2,4,5]
thank you
majid

Show 4 older comments
Walter Roberson on 29 Mar 2017
a(3) = [];
Rosie on 5 Jul 2017
Hi majed
You can use the follwoing
a(index)=[]
a(3)=[]
the number will delete
Good luck
Hamna Ameer on 29 Sep 2017
a(3)=[] how can i directly store this in a new vector say b?

Daniel Shub on 24 Sep 2012
Edited: MathWorks Support Team on 9 Nov 2018
I can think of three ways that are all slightly different
a=[1,2,3,4,5];
If you want to get rid of all cases where a is exactly equal to 3
b = a(a~=3);
If you want to delete the third element
b = a;
b(3) = [];
or on a single line
b = a([1:2, 4:end]);
Or, as Jan suggests:
a = [2,3,1,5,4]
a(a == 3) = []

Show 2 older comments
Walter Roberson on 16 Jun 2016
"Practical, fast and accurate!"
kwabena boafo-mensah on 8 Jul 2016
how does this work when i need to delete a range of row elements from a vector
Walter Roberson on 5 Jul 2017
b = a(a >= 2 & a <= 4); %keep 2 to 4

Jan on 24 Sep 2012
Edited: Jan on 24 Sep 2012
a = [1,2,3,4,5]
a(3) = []
Or:
a = [2,3,1,5,4]
a(a == 3) = []
These methods are explained exhaustively in the "Getting Started" chapters of the documentation. It is strongly recommended to read them completely. The forum is not though to explain the fundamental basics. Thanks.

Majid Al-Sirafi on 24 Sep 2012
thank you very much
Joel Bay on 28 Jun 2019
"These methods are explained exhaustively in the "Getting Started" chapters of the documentation."
Wrong, definetely not exhaustively after comparing Daniel's answer and the documentation. Logical indexing is not even mentioned. The answers to this question is still useful in 2019.

Andrei Bobrov on 24 Sep 2012
a = a(abs(a - 3) > eps(100))

1 Comment

Majid Al-Sirafi on 24 Sep 2012
than you very much

Elias Gule on 1 Dec 2015
% Use logical indexing
a = a(a~=3)

1 Comment

denny on 31 Aug 2017
I like this answer.