Finding a matrix representing points of sphere

I want try to use active contour algorithm in 3D.

For that I need initial boundary. I want to select initial boundary as sphere or ellipsoid.I can not use sphere function since it is in graphic format.

I need a matrix [Ax3] representing points on sphere. Where A is no of points

Answer 1

[Alan Stevens]

Why can't you use sphere? You can get your matrix as follows:

N = 19; A = (N+1)^2; R = 2;  % Example data with R as sphere radius
[X,Y,Z] = sphere(N);         
S = R*[X(:), Y(:), Z(:)];    % This is your Ax3 matrix

To see the result:

plot3(S(:,1),S(:,2),S(:,3),'.')