extract rows of a matrix

I have a matrix with many rows and 6 columns. I want to extract the rows whose 6th column == 1. How can I do this ? And what is this 'technique' called ? Logical indexing ? Find ? I keep forgetting how to do this. I need to refer to the documentation but im not sure what to google.

[Stephen23]

Logical indexing is faster than find.

Answer 1

[Stephen23]

 idx = 1==mat(:,6); % create logical vector
 out = mat(idx,:);  % use vector as logical index

http://blogs.mathworks.com/steve/2008/01/28/logical-indexing/

http://www.mathworks.com/help/matlab/math/matrix-indexing.html

http://www.mathworks.com/company/newsletters/articles/matrix-indexing-in-matlab.html

Answer 2

[Star Strider]

This works:

M = randi(9, 20, 6);
M_extract = M(M(:,6) ==1, :);