Solving values from 5 equations in MATLAB (4 variables)

[rayshaumik]

Hi, I have a problem in MATLAB. I am doing research in Optics ... I have to find 4 values from 5 equations and having some trouble. Please help.

I have tried reg this as below: I would be grateful to have any suggestions. Thanks in advance

clear

T = 0.89;
R = 0.11;
lamda = 0.98;
d = 1.65;
pi = 3.14;
phit = 0.6;
phir = 0.31;
%((-(a))*d) == (23.03)*k;

% sym a b n k; % a and b are "alpha" and "beta"

a = sym('a');
b = sym('b');
n = sym('n');
k = sym('k');

eq1 = T == '({(1-R)^2+4*R*(sin(phir))^2}*exp((-a)*d))/((1-R*exp((-a)*d))^2+4*R*exp((-a)*d)*(sin(b+phir))^2)';
eq2 = (phit) == '((2*(pi)*n*d)/lamda)-(atan((k(n^2+k^2-1))/((k^2+n^2)*(2+n)*n)))+(atan((R*exp((-a)*d))*(sin2(b+phir))/(1-R*exp((-a)*d)*cos2(b+phir))))';
eq3 = (phir) == 'atan(((-2)*k)/(1-((n)^2)-((k)^2)))';
eq4 = (b) == '((2*(pi)*n*d)/lamda)';
eq5 = (a) == '((4*(pi)*k)/lamda)';
%eq6 = (e) == '((-(a))*d) == (23.03)*k';

[a b n k] = solve(eq1,eq2,eq3,eq4,eq5,a,b,n,k);

 

[hate]

You are doing it the hard way imo. 5 equations for 4 variables means 1 of the equations is unnecessary assuming the system is consistent. So you may as well use the Cramer rule for ease of things in your case.

 

[_Eduardo_]

First you should research on algebra and systems of equations (linear and nonlinear). It's obvious what you do not know what you are doing.

Not only are more equations than unknowns (generally incompatible), but the relation is direct in some. That would eliminate equations for MATLAB happyness.