The first function shows a basic misunderstanding of MATLAB's indexing and arrays, which has nothing to do with functions per se. Lets have a look: function z= myfun(t)
z(1) = 10*t;
end
is called from the command window with this (after fixing the incorrect function name):
>> t = linspace(0,1,400);
>> z = myfun(t)
However this immediately produces an error, proving that you did not even try the code that you posted:
In an assignment A(I) = B, the number of elements in B and I must be the same.
What does this mean? This is because t is a vector of values (it has 400 elements!), whereas inside myyfun you are string to put 400 elements in one element z(1) with this allocation:
This will always be an error in MATLAB: every element must have its own position. One solution is to use some indexing , but the best options is to simply ignore the indexing altogether: This will then work without error.
But how can we fix the second function? In this case you actually want to use different t values on each function. There are many solutions to this, here are two that you could try:
1) an easy but not very good way would be to return one numeric matrix for each call of the function, with all values inside:
function z= myfun2(t)
z(1,:) = 10*t;
z(2,:) = 10*t.^2;
z(3,:) = 5*exp(-2*t);
end
2) a much better solution is to return function handles for each function, and evaluate these in the command window:
function fun = myfun2
fun{1} = @(t) 10*t;
fun{2} = @(t) 10*t.^2;
fun{3} = @(t) 5*exp(-2*t); fixed syntax mistake with exp
end
calling this function will return a cell array of functions handles : these can then be evaluated with whatever t values you want: >> fun = myfun2();
>> y = fun{2}(t)
