You can save them in separate .m files named according to the function, or you can write your code in one .m file using the structure
function main
....
end %notice this 'end' here
function firstfunction
...
end %notice this 'end' here
function secondfunction
...
end %notice this 'end' here
or you can write your code in one .m file using the structure
function main
...
function firstfunction %within the scope of main!
...
end %this 'end' is needed
function secondfunction %within the scope of main!
...
end %this 'end' is needed
...
end %this 'end' is needed
or you can write them in one .m file using the structure
function main
....
%no 'end'
function firstfunction
...
%no 'end' here either
function secondfunction
...
%no 'end' here either
The different choices have slightly different implications. Defining functions within the body of another function allows the subfunctions to share the variables of the containing function. The subfunction style can be mixed with the style that uses the explicit 'end' at the close of each routine. The subfunction style cannot be used in the style that leaves off the 'end' from the routines that share the same file. If you write several routines in the same file, then they either all must have 'end' or they must all not have 'end'.
You will not notice much difference between writing several routines in the same file with or without the explicit 'end', but if you use the 'end' then you cannot create new variables at run-time -- a limitation that allows more efficient code and better consistency checking.
Any routine saved in a separate file by itself can be called by another .m file, which is useful to build up a library of utility routines.
