Error " Array indices must be positive integers or logical values."

This is the Question I am being asked to solve and this is the code I have so far...

T1 = 70; %deg F
T2 = 200; %deg F
W = 2; %ft
L = 2; %ft
x = 1; %ft
y = 1; %ft

for n=0:1.83:11
T(n)=(T2-T1)*(2/pi)*(2/n)*(sin(n*pi*x/L))*(sinh(n*pi*y/L))/sinh(n*pi*W/L)+T1;
end

I'm nor sure if my n for the for loop is correct since nmax is 11 and there needs to be six steps, but I keep getting an Error " Array indices must be positive integers or logical values."

Not sure how I can fix the Error.

[Rik]

As a side note: if your code is correct, then the only "correct and appropriate" use of a loop will be be this:

for dummy=1
    T=%array operation that creates T
end

Answer 1

[Rik]

You need to distinguish between the index of your variable in Matlab and the subscript in the mathematical sense.

sub=___;%hint: look at linspace
for n=1:numel(sub)
    T(n)=___

[Jessica Larry]

Could you possibly elaborate? I'm not really understanding what you mean.

[Rik]

If you use T(n) in Matlab that can mean two things: you are calling a function with an input argument, or you have a variable and are extracting a value from it. These two interpretations are strictly separated.

You are trying to fill an array with values. You may want to say that T has a specific value for n=0.1, but that doesn't fit either description. So you what you have to do is to create two arrays: one will hold the values of n, the other will hold the respective values of T.

T(0.1) result in an error because T is not a function. Store that 0.1 in another array and use integers to index:

sub=[0.1 0.2];
T(1)=SomeFunction(sub(1));
T(2)=SomeFunction(sub(2));

%don't do T(0.1), but do this:
T(sub==0.1)

[Jessica Larry]

Oh ok that makes a lot of sense, thanks so much for the help!