I need help understanding this test file and how to use the modified secant method with it. Can someone explain what a(1) is referring to? and how can i use modified secant?

% This program is to test the Modified Secant for systems of equations

% section of your function.

h1 = @(a) a(1) + a(2) - 2;

h2 = @(a) a(1)*a(3) + a(2)*a(4);

h3 = @(a) a(1)*(a(3)^2) + a(2)*(a(4)^2) - 2/3;

h4 = @(a) a(1)*(a(3)^3) + a(2)*(a(4)^3);

handles = {h1, h2, h3, h4};

c_and_x_init = [0.5, -2, -0.25, 0.25];

% Should converge to

% c_and_x = [1, 1, 0.577350269189, -0.577350269189]

% or

% c_and_x = [1, 1, -0.577350269189, 0.577350269189]

c_and_x_final = KahunaB_Lab4(handles, c_and_x_init, 0.0000001)

[John D'Errico]

You need to write the code to do modifed secant mathod. Surely that was discussed in class. So look in your notes. Or look online.

https://uomustansiriyah.edu.iq/media/lectures/5/5_2018_01_14!04_32_56_PM.pdf

Surely you can find a link for pseudo-code for modified secant method. In fact, if you look, I'd bet you can find MATLAB code.

a is assumed to be a vector of length 4. a(1) refers to the FIRST element of a. If this is a surprise to you, then you strongly NEED to spend time doing the MATLAB Onramp tutorial.