pls explain me the star marked lines,i m not getting that

function fltimg_Callback(hObject, eventdata, handles)
% hObject    handle to fltimg (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
global im_n;
global im;
global im_sz;
global d;

WIN_sz=21;   ******************
ln=floor(WIN_sz/2);
A_mat=zeros(1,256);  **************

%%in the code there is not declared WIN_sz abd A_mat

Answer 1

[KSSV]

WIN_sz=21;   % Variable WIN_sz is assigned value 21
ln=floor(WIN_sz/2);
A_mat=zeros(1,256);  % A matrix/vector A_mat is initialized with zeros

[Komal Gaikwad]

but in the code WIN_sz in not declared anywhere and what does (1,256) stands?

[Stephen23]

@Komal Gaikwad: The MATLAB documentation states "You do not have to declare variables before assigning values to them."

source: https://www.mathworks.com/help/matlab/matlab_env/create-and-edit-variables.html

Those variables will simply be created when they are first allocated to.

[Image Analyst]

zeros() is a function. Click in it and type F1 to bring up help and it will tell you what all the input arguments mean.

[Komal Gaikwad]

thank you so much all of you.