The function return value 'value' might be unset.

I'm trying to make a code that uses Euler's method into a function that can be called later. This is the original, which works as intended.

K = 167; H = 100; Te = 20; w = 0.01; T(1) = 100;
t = 0.001; L = 0.4; A = w*t; P = 2*w + 2*t;
h = 0.1/100; x = [0:h:0.4];
V = -21277.8;
Tprime = @(V)V;
Vprime = @(T) (H*P*(T-Te))/(K*A);
 
for k = 1:length(x)-1
    T(k+1) = T(k) + h*Tprime(V(k));
    V(k+1) = V(k) + h*Vprime(T(k));
end
TL = T(k)
T(1:5)

And this is my attempt at making it into a function that can be called.

function value = Problem2B(V)
K = 167; H = 100; Te = 20; w = 0.01; T(1) = 100;
t = 0.001; L = 0.4; A = w*t; P = 2*w + 2*t;
h = 0.1/100; x = [0:h:0.4];
V = -21277.8;
Tprime = @(V)V;
Vprime = @(T) (H*P*(T-Te))/(K*A);
 
for k = 1:length(x)-1
    T(k+1) = T(k) + h*Tprime(V(k));
    V(k+1) = V(k) + h*Vprime(T(k));
end
TL = T(k)
T(1:5)
Problem2B = TL
end

But it gives me the error when I try to call it in other .m files.

Answer 1

[Star Strider]

Your function returns the variable ‘value’, however you never assign anything to ‘value’ in your function (at least not that I can see).

It seems that you want to return ‘T’ or ‘TL’. Consider assigning one of them to ‘value’.

Also, this line could cause problems:

Problem2B = TL

It would be best to delete it.