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I have an nx1 vector in Matlab. I want to delete rows starting from a specific index. For example, if n is 100 and the index is 60 then all rows from 60 till 100 will be removed. I've found this REMOVEROWS but I don't know how to make it do this.

Tak
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    This is pretty basic Matlab, but see [this question and answer](http://stackoverflow.com/questions/19633192/memory-efficient-way-to-truncate-large-array-in-matlab/19648283#19648283) for discussion on the best way (at the time at least) to do this: `a=rand(100,1);` `a=a(1:59);` – horchler May 26 '14 at 03:38
  • thanks! could you make this as an answer to mark it as solved? – Tak May 26 '14 at 03:42

2 Answers2

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The removerows function is probably overkill for a vector, but here is how it can be used along with the usual linear indexing method:

n = 100;
index = 60;
a = rand(n,1); % An n-by-1 column vector
b1 = a(1:index-1)
b2 = removerows(a,'ind',index:n) % Or removerows(a,'ind',index:size(a,1))

Note that the removerows function is in the Neural Network toolbox and thus not part of core Matlab.

horchler
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1

This should the trick:

your_vector(index:end) = [];

If you want to remove from the end that you can do:

your_vector(end-index+1:end) = [];
Marcin
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