MATLAB: I want to use the L0 norm

functionmatlab functionnorm

Hi !

I was trying to use the function norm(v,p). but p takes value from 1 to inf.

How can I calulate the zero norm ?

I used sum(x>0).

use cart2pol function

Is Pu a vector resulting from multiplying a vector by a matrix

P = randn(2,2);
u = randn(2,1);
norm(P*u,2)