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