# How to use Greek Letters in equation

5 views (last 30 days)
Aloe on 26 Jul 2022
Answered: Stephen23 on 26 Jul 2022
Hello
I am still new to MatLAB but below is my attempt on using greek letters in my equation. It comes up with an error saying "Invalid use of operator" and some other errors in connector which is confusing for me. Been trying to fix it but no hope.
Any help will be appreciated.
k1 = \omega .* sqrt((\mu .* \epsilon)/(2)) .* sqrt((1 + ((\sigma)/(\epsilon .* \omega))^2) + 1);
Invalid use of operator.

Error in connector.internal.fevalMatlab

Error in connector.internal.fevalJSON
k2 = \omega .* sqrt((\mu .* \epsilon)/(2)) .* sqrt((1 + ((\sigma)/(\epsilon .* \omega))^2) - 1);
k = k1 + i.*k2;
disp(k)
Aloe on 26 Jul 2022
@KSSV My equation has them as constants so I thought I could use them as constants like that

Stephen23 on 26 Jul 2022
The MATLAB approach:
syms omega mu epsilon sigma
k1 = omega .* sqrt((mu .* epsilon)/(2)) .* sqrt((1 + ((sigma)/(epsilon .* omega))^2) + 1);
k2 = omega .* sqrt((mu .* epsilon)/(2)) .* sqrt((1 + ((sigma)/(epsilon .* omega))^2) - 1);
k = k1 + i.*k2
k = ### More Answers (1)

Aloe on 26 Jul 2022
Edited: Aloe on 26 Jul 2022
I improved it and hope this makes it more right to be considered a code in MatLAB
omega = evalin(symengine, 'ω');
mu = evalin(symengine, 'µ');
epsilon = evalin(symengine, 'ϵ');
sigma = evalin(symengine, 'σ');
k1 = omega * sqrt((mu .* epsilon)/(2)) * sqrt((1 + ((sigma)/(epsilon * omega))^2)+1);
k2 = omega * sqrt((mu * epsilon)/(2)) * sqrt((1 + ((sigma)/(epsilon * omega))^2)-1);
k = k1 + 1i*k2;
disp(k) 