MATLAB: How to delete a row of a matrix if value in a particular column is less than a specified value

Question

say I have a 3×4 matrix

data = [5 1 200 33; 3 0.5 100 33; 4.5 1.5 150 33]

I want to delete the entire row if the value in 1st column is less than 4.

it should return a 2×4 matrix looking like the following:

datanew = [5 1 200 33; 4.5 1.5 150 33]

I am going to apply this to a much larger matrix, like 10000×4 size, and think a loop is the way to go, but I am unsure on how to go about it.

Thanks Bob

Answer 1

Hello,

You can use this one liner,

datanew = data(data(:,1)>=4,:);

However, I chose to reverse the logic here, so instead of less than 4, you should write greater than or equal to (it's selecting the ones to keep).

Also, the data(:,1) is using the first column (just to be clear).

Hope this helps!