Hi,

I'm trying to figure out a way to properly update the guess (from the initial within a range of 1 to 3) for a bessel function (1st and 2nd kind) that I'm solving roots/eigenvalues for as I go through the loop. Below is a section of my code that I'm currently having trouble in trying to initiate the correct second guess where the function is zero:

`R_i = 3;R_o = 13;x0 = 1;for i = 1:5 for j = 1:4 m = modes(j); k = modes(j+2); x = x0; fun = @(mu) (0.5*(besselj(m,mu*R_o)-besselj(k,mu*R_o)))*(0.5*(bessely(m,mu*R_i)-bessely(k,mu*R_i))) ... - (0.5*(besselj(m,mu*R_i)-besselj(k,mu*R_i)))*(0.5*(bessely(m,mu*R_o)-bessely(k,mu*R_o))); eig(i,j) = fzero(fun,x); %solve for the zeros of the function`

mu_guess(i,j) = eig(i,j); %storing all eigenvalues

x0 = i; %update guess per loop

endend

Appreciate any help I can get. Thanks!

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