How to make an if/else statement

My data file consists of 3 columns and 100,000 rows. I want my code to go down a series of rows and test each row for the following.

if column1 > 13 & column1 < 15

          put all those rows in a matrix (including columns 2 & 3) 

elseif column1 > 2 & column1 < 4

          put all these rows in a different matrix (including columns 2 & 3)

      end

What's a good approach to this?

Answer 1

[Guru]

FIND with the conditions is actually the way to do this.

% First read in your data file into MATLAB, let's say variable A
I1 = find(A(:,1) > 13 & A(:,1)<15);
I2 = find(A(:,1) > 2 & A(:,1) < 4);

% Now that you know the rows you want to assign, simply assign them...
B = A(I1,:);
C = A(I2,:);

HTH

Answer 2

[Kelly Kearney]

No if/else needed... just some logical indexing:

a = rand(100000,3)*15;
b = a(a(:,1)>13 & a(:,1)<15,:);
c = a(a(:,1)>2 & a(:,1)<4,:);