Complex Arithmetic: In the Intersection of C and C++

Listing 2: Test program

// Test program for math-complex.h.  This file can be
// compiled by either C99 or C++.

#include <stdio.h>
#include "math-complex.h"

static const long double pi =
  3.141592653589793238462643383279502884197L;

int main()
{
    // The three complex types store two components of the
    // underlying floating point type.
    printf("sizeof(float)=%2d        sizeof(float_complex)=%2d\n",
      (int) sizeof(float), (int) sizeof(float_complex));
    printf("sizeof(double)=%2d       sizeof(double_complex)=%2d\n",
      (int) sizeof(double), (int) sizeof(double_complex));
    printf("sizeof(long double)=%2d  sizeof(long_double_complex)=%2d\n",
      (int) sizeof(long double), (int) sizeof(long_double_complex));

    double_complex x, y, z;

    x = double_complex(1,2);
    y = double_complex(2,2);

    // You may mix complex and the corresponding real type
    z = x + y + 10.0;
    printf("(1+2i)+(2+2i)+10 = %g+%gi\n", real(z), imag(z));

    // But different complex types must be cast to a
    // common type or C++ rejects the program.
    long_double_complex w = long_double_complex(2,3);
    x = (double_complex) w * double_complex(5, 6);
    printf("(2+3i) * (5+6i) = %g+%gi\n", real(x), imag(x));
    x /= double_complex(5, 6);
    printf("(-8+27i) / (5+6i) = %g+%gi\n", real(x), imag(x));

    // e raised to the imaginary pi power is -1
    w = exp(long_double_complex(0., pi));
    printf("exp(pi*i) = %Lf+%Lfi\n", real(w), imag(w));

    // log of -1 is imaginary pi
    w = log(long_double_complex(-1, 0));
    printf("complex log(-1) = %Lf+%Lfi   (difference from pi=%Lg)\n",
      real(w), imag(w), imag(w) - pi);

    // absolute value of a complex number is a real number:
    // the square root of the sum of the squares of the real
    // and imaginary parts
    printf("abs(float_complex(3,4)) = %f\n", abs(float_complex(3,4)));

    // You may raise a real number to a complex power
    x = pow(exp(1.0), double_complex(0., pi));
    printf("e to the imaginary pi power = %f+%fi\n",
      real(x), imag(x));

    // Or a complex number to a real power
    x = pow(double_complex(0, 1), 2.0);
    printf("i squared = %f+%fi\n",
      real(x), imag(x));

    // Or a complex number to a complex power
    x = pow(double_complex(1, 1), double_complex(1, 1));
    printf("(1+1i) to the power (1+1i) = %f+%fi\n",
      real(x), imag(x));

    // Finally, square roots of negative numbers...
    x = sqrt(double_complex(-1.0, 0));
    printf("square root of -1 = %g+%gi\n",
      real(x), imag(x));

    // arg() returns the angle 
    long double ld = arg(long_double_complex(1., 1.));
    printf("arg(1+1i) = %Lf   (difference from pi/4=%Lg)\n", 
      ld, pi/4 - ld);

    // the conjugate of a complex number is the number with the
    // imaginary part's sign reversed.
    x = conj(double_complex(2., 3.));
    printf("conj(2+3i)) = %g+%gi\n",
      real(x), imag(x));

    // The complex trigonometric and hyperbolic functions
    x = double_complex(1,1);
    y = cos(x);
    printf("cos((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    y = sin(x);
    printf("sin((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    y = tan(x);
    printf("tan((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    y = cosh(x);
    printf("cosh((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    y = sinh(x);
    printf("sinh((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    y = tanh(x);
    printf("tanh((1+1i)) = %f+%fi\n",
      real(y), imag(y));

    return 0;
}