Convert numeric values to logicals
Pick out the odd-numbered elements of a numeric matrix.
Create a numeric matrix.
A = [1 -3 2;5 4 7;-8 1 3];
Find the modulus, mod(A,2), and convert it to a logical array for indexing.
L = logical(mod(A,2))
L = 1 1 0 1 0 1 0 1 1
The array has logical 1 (true) values where A is odd.
Use L as a logical index to pick out the odd elements of A.
ans = 1 5 -3 1 7 3
The result is a vector containing all odd elements of A.
Use the logical NOT operator, ~, on L to find the even elements of A.
ans = -8 4 2
Most arithmetic operations involving logical arrays return double values. For example, adding zero to a logical array returns a double array.
Logical arrays also are created by the relational operators (==,<,>,~, etc.) and functions like any, all, isnan, isinf, and isfinite.