I am finding error while writting code of tridiagonal matrix as my matlab do not konw what is tridiagonal

function x = Tridiagonal(e,f,g,r)
% Tridiagonal: Tridiagonal equation solver banded system
% x = Tridiagonal(e,f,g,r): Tridiagonal system solver.
% input:
% e = subdiagonal vector
% f = diagonal vector
% g = superdiagonal vector
% r = right hand side vector
% output:
% x = solution vector
n=length(f);
% forward elimination
for k = 2:n
    factor = e(k)/f(k-1);
    f(k) = f(k) - factor*g(k-1);
    r(k) = r(k) - factor*r(k-1);
end
% back substitution
x(n) = r(n)/f(n);
for k = n-1:-1:1
    x(k) = (r(k)-g(k)*x(k+1))/f(k);
end

getting error as follows:

> Tridiagonal

Not enough input arguments.

Error in Tridiagonal (line 11)

n=length(f);

Answer 1

[KSSV]

Do not run th function as code i.e. you are running the code with f5 or using the run button. You need to give inputs to the function and then call it.

% Example
e = value ;  % define your variable
f = value ;  % define your variable 
g = value ;  % define your variable 
r = value ;  % define your variable
% call your function
x = Tridiagonal(e,f,g,r) ; 

[Aman Murkar]

this is to plot tridiagonal matrix ? right

[KSSV]

Where plot come into picture? This is answer for the question you have asked.

[Aman Murkar]

bro my main issue is that i am tying to run code for differnet numerical methods where in program there is a function of tridiagonal matrix, after running code it shows error as unrecognized function ' tridiagonal'.

[Aman Murkar]

for that I was running above code to define what is tridiagonal

[KSSV]

The question you asked here conveys different. When running code, see to it that the function is saved in the same folder where you are running the code. Or add path of this function.