how to understand .sc .mat in matlab

Hello,i cant see the logic of these two lines taken from the full code shown bellow.

i know that its some how plotting an area but .mat .sc are resembling . command from c# of object oriented.

How to understand the meaning of the two lines shown bellow?

Is there any material i could use explaining examples for this structs?

Thanks

func_in.mat=NmidCirc;
func_in.sc=scale;

full code:

lambda=633e-9;% wave length in [m]
L=0.01;% meter factor, it is defined that 1cm=1024 pixels-> the first scale will be over 1cm
scale=linspace(-L/2,L/2,n);% basic scaling vector in length of 1024.
%% Q2 creating matrix
[X, Y]= meshgrid(scale,scale);% creating the basic function. on the function we will create the images that will operated
midCirc= X.^2+Y.^2<(1/n)^2;%because we work in meter units, the 100/1024[cm] transforms into 1/1024[m]
NmidCirc=not(midCirc);
Ring= ((X-0.8/n).^2+(Y-0.8/n).^2<(1/n)^2)&((X-0.8/n).^2+(Y-0.8/n).^2>(0.6/n)^2);
NRing=not(Ring);
Tshape= (abs(Y)<0.2/n)&(abs(X)<0.6/n) | ((Y<1.4/n)&(Y>0.2/n)&(abs(X)<0.2/n))


%%%% Negative cirle part
func_in.mat=NmidCirc;
func_in.sc=scale;
figure(2)
colormap gray
for j=1:6
     func_out=Rdiv(func_in,lambda,Z(j),n);
     subplot(2,3,j);
     image(func_out.sc, func_out.sc, abs(func_out.mat), 'CDataMapping','scaled');
     xlabel('[m]');
     ylabel('[m]');
     title(['Z=',num2str(Z(j))]);
end

Answer 1

[Jan]

The command func_in.mat = ... creates the struct "func_in" with the field "mat". See:

doc struct

A web search is a good strategy also, e.g. for "Matlab struct":

• https://www.mathworks.com/help/matlab/structures.html
• https://www.mathworks.com/help/matlab/matlab_prog/create-a-structure-array.html
• https://www.mathworks.com/videos/introducing-structures-and-cell-arrays-101508.html