You may declare that a VARIABLE name represents a complex quantity. The format of a complex declaration is:
variable_name = COMPLEX ( real_name , imaginary_name )
This declaration tells FlexPDE that variable_name represents a complex quantity, and assigns the real_name and imaginary_name to the real and imaginary parts of variable_name. You may subsequently assign EQUATIONS and boundary conditions either to the variable_name, or to its components individually. Similarly, you can perform arithmetic operations or request graphical output of either the variable_name itself, or its components individually.
C = COMPLEX(Cr,Ci)