Multiple functions working together?

here is my code in a script coding window:

function [n] = n(x)

syms q

[n]=(q^(x/2)-q^(-x/2))/(q^(1/2)-q^(-1/2));

end

function d=d(x)

d=n(x+1)

end

I then save this and go to the command window and type in d(3), which I would like the output to be equal to n(4), but instead I get this:

Index exceeds the number of array elements (1).

Error in sym/subsref (line 870)

R_tilde = builtin('subsref',L_tilde,Idx);

What the heck is going on!!? I'm new to this, help appreciated!

Answer 1

[Star Strider]

MATLAB is interpreting:

d(3)

as indexing into the third element of ‘d’.

Run:

which d -all

from a script or your Command Window to see if MATLAB can locate the ‘d’ function in the search path (preferably on your user path).

Answer 2

[David Hill]

syms q
n=@(x)(q^(x/2)-q^(-x/2))/(q^(1/2)-q^(-1/2));
d=@(x)n(x+1);

[Michael Vaughan]

what does the (x) do after the @ symbol???? Is it necessary? I seem to be giving functions handles without including that and it works fine