Hello everyone, I am fairly new to MATLAB. I have to approximate a root of a given function with Newton-Raphson method.(adsbygoogle = window.adsbygoogle || []).push({});

I have a code that looks like this: (newton.m)

What do I do now? I really need some help here. Do I need to define f and df first? And how?Code (Text):function [p0,err,k,y] = newton(f,df,p0,delta,epsilon,max1)

%Input - f is the object function

% - df is the derivative of f

% - p0 is the initial approximation to a zero of f

% - delta is the tolerance for p0

% - epsilon is the tolerance for the function values y

% - max1 is the maximum number of iterations

%Output - p0 is the Newton-Raphson approximation to the zero

% - err is the error estimate for p0

% - k is the number of iterations

% - y is the function value f(p0)

%If f and df are defined as M-file functions use the @ notation

% call [p0,err,k,y]=newton(@f,@df,p0,delta,epsilon,max1).

%If f and df are defined as anonymous functions use the

% call [p0,err,k,y]=newton(f,df,p0,delta,epsilon,max1).

% NUMERICAL METHODS: Matlab Programs

% (c) 2004 by John H. Mathews and Kurtis D. Fink

% Complementary Software to accompany the textbook:

% NUMERICAL METHODS: Using Matlab, Fourth Edition

% ISBN: 0-13-065248-2

% Prentice-Hall Pub. Inc.

% One Lake Street

% Upper Saddle River, NJ 07458

for k=1:max1

p1=p0-f(p0)/df(p0);

err=abs(p1-p0);

relerr=2*err/(abs(p1)+delta);

p0=p1;

y=f(p0);

if (err<delta)|(relerr<delta)|(abs(y)<epsilon),break,end

end

Thanks.

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# MATLAB function help!

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