Sea wave lengths calculation using Newton-Rapshon Iteration

I made this script to calculating wavelength from input wave period and water depth. using newton rapshon iteration. the equation is basically from the dispersion relation of linear wave theory.
soo check this awt!! I hope this would usefull :3

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clc ; clear all ; close all;
% Calculating wave number using iteration method : newton raphson 
% Meirita R. | mei.ramdhani@gmail.com


%INPUT
T       = [10];   % s   --> Wave Period
g       = 9.8 ;   % m/s --> Gravity constant.
h       = 10 ;    % m   --> depth.

sigma2  = (2*pi()/T)^2 ; %--> agular frequency.

syms k ;                 %--> desired wave number.

% dispersive eq. based on linear wave theory
d=k*tanh(h*k)-(sigma2/g);
f=inline(d)

% derivatives of dispersive eq. based on linear wave theory 
z=diff(d,k); 
f1=inline(z)


% input initial value for k 
x0=9;
x=x0;

% iteration process  
for u=0:100
    y=x;
    x=y-[f(x)/f1(x)]; 
    if x==y break 
    end
end

% WAVE NUMBER
wavenum =x
%WAVE LENGTH:
L(i)=(2*pi())/wavenum
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