The complex package provides ways to perform arithmetic operations,
  such as initialization, assignment, input, and output, on complex
  values (that is, numbers with a real part and an imaginary part).
  Additionally, this package supports operations that are unique to
  complex values, such as principal argument operations, conjugate
  operations, and conversions to and from polar coordinates.

  With the c_exception class and its c_exception function, the complex
  package also provides a mechanism for reporting and handling complex
  arithmetic errors.

  Header:

 	#include <complex.hxx>

1 - Global Declarations

  The following declarations are used by the complex package but they
  are not members of a particular class:

  typedef int (*cxxl_p_complex_error_t)(c_exception &error_information);
  static const complex_zero (0, 0);
  cxxl_p_complex_error_t set_complex_error(cxxl_p_complex_error_t p_complex_error

2 - complex

  This class contains methods to perform complex value operations.
  These include arithmetic, assignment, and comparison operators for
  complex values; Cartesian and polar coordinates; mixed-mode
  arithmetic; and mathematical functions for complex values equivalent
  to standard mathematical functions.

3 - c_exception

  Objects of this class handle exceptions for complex arithmetic. This
  includes information on functions, parameters, error types, and
  default return values.