complex::complex

Constructs a complex number with specified real and imaginary parts or as a copy of some other complex number.

complex(
    const Type& _RealVal = 0, 
    const Type& _ImagVal = 0
);

template<class Other>
   complex(
      const complex<Other>& _ComplexNum
      );

Parameters

• _RealVal
  The value of the real part used to initialize the complex number being constructed.

• _ImagVal
  The value of the imaginary part used to initialize the complex number being constructed.

• _ComplexNum
  The complex number whose real and imaginary parts are used to initialize the complex number being constructed.

Remarks

The first constructor initializes the stored real part to _RealVal and the stored imaginary part to _Imagval. The second constructor initializes the stored real part to _ComplexNum**.real**() and the stored imaginary part to _ComplexNum**.imag**().

In this implementation, if a translator does not support member template functions, the template:

template<class Other>
   complex(const complex<Other>& right);

is replaced with:

complex(const complex& right);

which is the copy constructor.

Example

// complex_complex.cpp
// compile with: /EHsc
#include <complex>
#include <iostream>

int main( )
{
   using namespace std;
   double pi = 3.14159265359; 

   // The first constructor specifies real & imaginary parts
   complex <double> c1 ( 4.0 , 5.0 );
   cout << "Specifying initial real & imaginary parts,"
        << "c1 = " << c1 << endl; 

   // The second constructor initializes values of the real &
   // imaginary parts using those of another complex number
   complex <double> c2 ( c1 );
   cout << "Initializing with the real and imaginary parts of c1,"
        << " c2 = " << c2 << endl; 

   // Complex numbers can be initialized in polar form
   // but will be stored in Cartesian form
   complex <double> c3 ( polar ( sqrt( (double)8 ) , pi / 4 ) );
   cout << "c3 = polar ( sqrt ( 8 ) , pi / 4 ) = " << c3 << endl; 

   // The modulus and argument of a complex number can be recovered
   double absc3 = abs ( c3 );
   double argc3 = arg ( c3 );
   cout << "The modulus of c3 is recovered from c3 using: abs ( c3 ) = "
        << absc3 << endl;
   cout << "Argument of c3 is recovered from c3 using:\n arg ( c3 ) = "
        << argc3 << " radians, which is " << argc3 * 180 / pi
        << " degrees." << endl;
}

Output

Specifying initial real & imaginary parts,c1 = (4,5)
Initializing with the real and imaginary parts of c1, c2 = (4,5)
c3 = polar ( sqrt ( 8 ) , pi / 4 ) = (2,2)
The modulus of c3 is recovered from c3 using: abs ( c3 ) = 2.82843
Argument of c3 is recovered from c3 using:
 arg ( c3 ) = 0.785398 radians, which is 45 degrees.

Requirements

Header: <complex>

Namespace: std

See Also

Concepts

complex Class

complex Members