The explanation of each step in ellipse fitting code

I need help understanding each line of this code.

% Calculate centroid, orientation and major/minor axis length of the ellipse
s = regionprops(BW,{'Centroid','Orientation','MajorAxisLength','MinorAxisLength'});
% Calculate the ellipse line
theta = linspace(0,2*pi);
col = (s.MajorAxisLength/2)*cos(theta);
row = (s.MinorAxisLength/2)*sin(theta);
M = makehgtform('translate',[s.Centroid, 0],'zrotate',deg2rad(-1*s.Orientation));
D = M*[col;row;zeros(1,numel(row));ones(1,numel(row))];

Answer 1

[Matt J]

I've added some comments.

% Calculate centroid, orientation and major/minor axis length of the ellipse
s = regionprops(BW,{'Centroid','Orientation','MajorAxisLength','MinorAxisLength'}); 

theta = linspace(0,2*pi);
col = (s.MajorAxisLength/2)*cos(theta);
row = (s.MinorAxisLength/2)*sin(theta); %coordinates of points (col,row) on unrotated ellipse



M = makehgtform('translate',[s.Centroid, 0],'zrotate',deg2rad(-1*s.Orientation)); %rotation matrix

D = M*[col;row;zeros(1,numel(row));ones(1,numel(row))];%points on rotated ellipse

[Walaa]

thanks you

[Matt J]

You are quite welcome.