How to delete rows where one element is forced to meet some criteria off of a 2xn array

Hey all. I did a good deal of searching, but I'm having some trouble removing specified elements of an array. Basically, I have a 'time' coordinate as one column, and a measurement as the other. I was hoping to find all those measurement values greater than some threshold, and keep them (ie toss those that don't meet that).

Two things I've tried:

A = [time column, measurement column]

B = A(A(:,2)>threshold)

But this only returns the threshold values.

for n =1:size(A(1)),
    if A(n,2) < threshold,
        A(n,2) = []
    end
end

Attempting to delete the part of the array that is below threshold. Thanks for any input!

Answer 1

[Azzi Abdelmalek]

A = [time column, measurement column]
B = A(A(:,2)>threshold,:)

Answer 2

[Wayne King]

I'll make up some data and show you (there are many ways to do this)

 A = ones(20,2);
 A(:,2) = randi([0 10],20,1);
 A(:,1) = 1:20;

Threshold is 5

 idx = find(A(:,2)>5);
 B = A(idx,:);

Or

C = A(A(:,2)>5,:);

Of course, your time column is now not going to be evenly spaced.