MaplePrimes - answers and comments on Question, How can I solve a system of Differential Algebraic Equations with COMPLEX intial condition value?

real and imaginary parts

Robert Israel — Mon, 19 Oct 2009 22:11:01 Z

I suspect you'll want to look at the real and imaginary parts. Replace any variable z(t) that will be complex with x(t) + I*y(t),
and use evalc(Re(...)) and evalc(Im(...)) to take real and imaginary parts of your equations, giving you a system of DAE's for real variables.

My system is real itself,

nmani — Mon, 19 Oct 2009 23:28:16 Z

My system is real itself, just initial condition are complex.

I mean the value I have for initial value are complex but system is real what should I do now?

Thanks

Complex

Robert Israel — Tue, 20 Oct 2009 22:09:01 Z

The system may look real, but if there are complex initial conditions the variables that have those initial conditions will be complex.
If your system is linear with real coefficients, there will be separate equations for real and imaginary parts of the variables. If it is nonlinear, you'll have equations in which the real and imaginary parts will be coupled.