Delete rows from a matrix using for loop

Hello, I need delete rows from a matrix based on a logical condition of an array using for loops:

I need delete rows from this matrix:

Matrix = [ 1,1 ; 1,2 ; 1,3 ; 2,1 ; 2,2 ; 2,3 ];

Based on this array:

Vec = [0,-0.5,-1,0.5,0,-0.5];

if any element of Vec is < 0, I need delete the index rows of this condition from the Matrix.

And I need a new matrix

MatrixAux = [1,1 ; 1,3 ; 2,2];

I try this code:

LM = length(Matrix);

MatrixAux [];

for i =1: LM

if Vec(i) < 0

MatrixAux(i,:) = Matrix(i,:);

end

end

Any idea?

Answer 1

[Voss]

The MatrixAux in your example doesn't seem to correspond to the process you decribe. Maybe I'm misunderstanding, but it seems like you can do this (no for loops required):

Matrix = [ 1,1 ; 1,2 ; 1,3 ; 2,1 ; 2,2 ; 2,3 ];   
Vec = [0,-0.5,-1,0.5,0,-0.5];

idx_to_delete = Vec < 0;
Matrix(idx_to_delete,:) = [];

disp(Matrix);

     1     1
     2     1
     2     2

or more simply:

Matrix = [ 1,1 ; 1,2 ; 1,3 ; 2,1 ; 2,2 ; 2,3 ];   
Vec = [0,-0.5,-1,0.5,0,-0.5];

Matrix(Vec < 0,:) = [];

disp(Matrix);

     1     1
     2     1
     2     2