Torsten
Posts:
1,639
Registered:
11/8/10


Re: complicated equation including bessel functions
Posted:
May 8, 2013 4:18 AM


"ghasem " <shaban_sadeghi@yahoo.com> wrote in message <kmbkid$pni$1@newscl01ah.mathworks.com>... > 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)(1eps1)*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
What variables are changed within your forloop ? The complex constants eps1, k0, k1 and k2 ?
Best wishes Torsten.

