# Removing entries of vector indexed by odd integer.

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David on 25 Sep 2013
So, in a question we've been asked to define a vector "x" which begins at 1.5 and ends at -3.5 with 101 entries in between without the use of any loops. So, I used linspace(1.4, -3.5, 101) to do this. However the next part of the question requires you to create a matrix "y" which corresponds to "x" only with the entries indexed by an odd integer removed. How can you do this without using a loop? Is there a function for it? Thanks.

Leah on 25 Sep 2013
You just have to reference every other element of the vector you created.
x=linspace(1.4, -3.5, 101) ;
y=x(1:2:end);

#### 1 Comment

David on 25 Sep 2013
Will that not include elements 1 and 101 though, and they're odd indexes? Why wouldn't it be y = x(2:2:100);?

Matt J on 25 Sep 2013
Edited: Matt J on 25 Sep 2013
x=linspace(1.4, -3.5, 101) ;
y=x;
y(1:2:end)=[];
or
y=x(2:2:end);

Image Analyst on 25 Sep 2013
It gets elements, 2,4,6,8,10,12,14,........98,100,102. It can't get 104 since there is no 104, and since it doesn't get odd numbers, it won't get 103 even though it is "end" because it is odd. Does that explain it better?
Matt J on 25 Sep 2013
>> 2:2:15
ans =
2 4 6 8 10 12 14
David on 25 Sep 2013
Brilliant! Thanks a million.