A small complex package
I have written a small (inefficient; why is it?) package which you can use to compute with complex numbers. Fortran has a built-in datatype for complex number, for C has not.
Here is a list of the prototypes and a short description of the routines.
To make the prototypes (and the definition of the type Complex) available to your program include the following line in the beginning:
#include "defs.h"
Complex Add(Complex z, Complex w)
Returns z + w.
Complex Sub(Complex z, Complex w)
Returns z - w.
Complex Mul(Complex z, Complex w)
Returns z * w.
Complex Div(Complex z, Complex w)
Returns z / w.
In the following calls a is not complex but real.
Complex Adds(double a, Complex z)
Returns a + z.
Complex Muls(double a, Complex z)
Returns a * z.
Complex Divs(double a, Complex z)
Returns a / z.
void PrintC(Complex z)
Print z.
double Cabs(Complex z, Complex w)
Returns |real(z) - real(w)| + |imag(z) - imag(w)|. Can be used
to terminate the iteration (if two iterands are close enough, or the iterand
is close to a root).
Complex Exp(Complex z);
Returns exp(z).
Complex Double2Complex(double re, double im)
Return the complex number having real part re and imaginary
part im.
A complex number can be created using the following syntax (using the
function Double2Complex):
Complex z, w = {1.0, -2.5};
z = Double2Complex(2.3, 4.5);