How do i count a certain class of numbers in a 100x100 matrix?

I wrote this code and i want to count the number of non imaginary numbers in the matrices za and zb. is there a way to count through the elements of a matrix? or do i now have to use a for loop?

I had to do a vaktorization already, because with a for loop it took 0.4 sec per iteration. so if you find any error please tell me about it also.

 %define simulation variables
  N=10000; %<--- PLEASE SET NUMBER OF RAYS <-----
  M=0; %numberhits

%define Geometry
r1= 10; %radius sphere
r2=10; %radius disk
h=20; %height sphere center

 %Analytic solution viewfactor disk sphere
F21ana= 2*(1-1/(sqrt(1+(r2/h)^2)))*(r1/r2)^2
 %determines the viewfactor disk to sphere
n=[0;0;-1];
t1=[1;0;0];
t2=[0;1;0];

    R1= rand(sqrt(N));
    R2= rand(sqrt(N));
    r=r2*sqrt(R1);
    phi=2*pi()*R2;
  %create the coordinates of the point on disk  
    x2=r*cos(phi);
    y2=r*sin(phi);
    z2=h;

    R1= rand(sqrt(N));
    R2= rand(sqrt(N));
    thet=sin(sqrt(R1))^-1;
    phi=2*pi()*R2;

%create the direction vector of the ray

   ux=sin(thet)*cos(phi);
   uy=sin(thet)*sin(phi);
   uz=-1*cos(thet);

%define variables for equation system
 A=1+(uy./uz).^2 + (ux./uz).^2;
 B=-2*z2*( (uy./uz).^2 + (ux./uz).^2) + 2*y2*uy./uz +2*x2*ux./uz;
 C=y2^2 + x2^2 - r1^2 +z2^2*( (uy./uz).^2 + (ux./uz).^2)-z2*( 2*y2*uy./uz +2*x2*ux./uz);
%solve system
za= (-B + sqrt(B.^2 - 4*A.*C))./(2*A);
zb= (-B + sqrt(B.^2 + 4*A.*C))./(2*A);

Answer 1

[Cedric Wannaz]

 >> sum(~imag(za(:)))
 ans =
        8627

[O Mueller]

like this it works kind of.

   z=[za zb];
   M= sum(imag(z(:))~=0);

[Cedric Wannaz]

Just do it on both arrays:

 >> n_za = sum(~imag(za(:))) ;
 >> n_zb = sum(~imag(zb(:))) ;

or

 >> n_tot = sum(~imag(za(:))) + sum(~imag(zb(:))) ;