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Topic: complicated equation including bessel functions
Replies: 22   Last Post: May 8, 2013 2:43 PM

 Messages: [ Previous | Next ]
 ghasem Posts: 118 Registered: 4/13/13
complicated equation including bessel functions
Posted: May 7, 2013 3:27 PM

Hi.
how solve an complicated equation including bessel functions,when my unknown and my initial guesses are complex?
my code is as following: (is within a for loop)

syms bet % bet is my unknown
for i = 1: 100
% eps1 , k1,k2,k0 are complex constant.
gam = sqrt(bet^2 - k1^2);
T = sqrt(bet^2 - k2^2);
tau = sqrt(bet^2 - k0^2);
%
X1 = gam*besseli(0,gam);
X2 = T*(eps1*besseli(1,gam)-(1-eps1)*gam.*besseli(0,gam));

X3 = -T*tau*bessely(0,T)*besselk(1,tau)-...
tau^2*bessely(1,T)*besselk(0,tau);
X4 = -T*tau*besselj(0,T)*besselk(1,tau)-...
tau^2*besselj(1,T)*besselk(0,tau);

exp1(i) = X1.*(besselj(1,T).*X3 - bessely(1,T).*X4)-...
X2.*(besselj(0,T).*X3 - bessely(0,T).*X4);

my_guess = (i/100) +1j*(k0+(i/m));
exp2(i) = fsolve(@(bet)eval(exp1(i)),guess);

real_ans(i) = real(exp2(i));
imag_ans(i)= imag(exp2(i));
end
====================================
I think that fsolve is not exact.because my answers are not simillar to my reference.
is there any better method,instead fsolve?
ghasem

Date Subject Author
5/7/13 ghasem
5/8/13 ghasem
5/8/13 Torsten
5/8/13 Bruno Luong
5/8/13 Torsten
5/8/13 ghasem
5/8/13 Bruno Luong
5/8/13 ghasem
5/8/13 Nasser Abbasi
5/8/13 Bruno Luong
5/8/13 ghasem
5/8/13 Torsten
5/8/13 ghasem
5/8/13 Torsten
5/8/13 Bruno Luong
5/8/13 ghasem
5/8/13 Bruno Luong
5/8/13 ghasem
5/8/13 Steven Lord
5/8/13 ghasem
5/8/13 Steven Lord
5/8/13 ghasem
5/8/13 ghasem