# removing rows containing certain values

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Seth on 28 Mar 2016
Edited: Kirby Fears on 28 Mar 2016
i have a 3X3 matrix and i want to delete rows containing values greater than a certain value and values less than another certain value, then store the deleted rows separately. These values lie on the second and third column. thank you

Kirby Fears on 28 Mar 2016
Edited: Kirby Fears on 28 Mar 2016
Seth,
You can create logical indexes with conditional statements, and use the & for "and" as well as | for "or" to combine conditions. The resulting logical index can be used for indexing. Here's an example:
m = magic(3);
idx = (m > 8) | (m < 3);
% using "find" to identify rows where logical idx is true
[delRows,~] = find(idx);
% remove duplicates
delRows = unique(delRows);
% store deleted rows
m_toDelete = m(delRows,:);
% delete rows
m(delRows,:) = [];
Hope this helps.
Kirby Fears on 28 Mar 2016
The method from Azzi's answer is more efficient:
m = magic(3);
idx = any((m > 8) | (m < 3),2);
% store deleted rows
m_toDelete = m(idx,:);
% delete rows
m(idx,:) = [];

Azzi Abdelmalek on 28 Mar 2016
Edited: Azzi Abdelmalek on 28 Mar 2016
A=rand(3,3)
idx=any(A<0.1 | A>0.9,2)
out=A(idx,:)
A(idx,:)=[]