Torsten
Posts:
1,450
Registered:
11/8/10


Re: complicated equation including bessel functions
Posted:
May 8, 2013 9:50 AM


"ghasem " <shaban_sadeghi@yahoo.com> wrote in message <kmdjg7$ga8$1@newscl01ah.mathworks.com>... > > > How convert this equation to real and imaginary parts? > > > I can not,because I arguments of bessel functions are complex.foe example: > > > besseli(1,2+3*j) > > > how separate for real and imaginary parts? > > > ghasem > > > > instead of > > z > besseli(1,z) > > > > consider > > (x,y) > (real(besseli(1,z), imag(besseli(1,z))), where z = 1+1iy. > > > > The later function is R^2 > R^2, even intermediately it's a 1D complex function Z > Z. > ================================== > thank you Mr abbasi and Bruno > BUT,I think that you don't understand my equation. > argument of bessel functions are complex,and also my unknown ('bet') is within these arguments. > So,when you use from: > real(besseli(1,z)) or,in total: > real(my_final_equation) > in fact you separate only real and imaginary parts in out of argument.but,my complex unknown exist within bessel arguments,aslo. > So,when I introduce "syms bet" and write the code and finally use from: > exp2(i) = fsolve(@(bet)eval(exp1(i)),my_guess); > in fact,"bet" unknown is a parameter (inexp1(i)) equation),and MATLAB with real and imag command,can not separate real and imaginary parts of "bet". > it is clear my explanations? > thank you very much for your attention... > ghasem
You solve in _two_ unknowns: bet_real and bet_imag. You evaluate your bessel functions for z=bet_real+1j*bet_imag. You return the real and imaginary part of exp1(i) to fsolve. (Two equations in two unknowns).
Best wishes Torsten.

