complex::complex

构造一个复数使用指定的物理和虚拟部分或作为某些其他复数的副本。

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

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

参数

• _RealVal
  用于的实部的值初始化构造的复数。

• _ImagVal
  使用的虚拟部分中的值初始化构造的复数。

• _ComplexNum
  物理和虚拟部分用于初始化构造的这个复数的复数。

备注

第一个构造函数初始化该存储的实部到_RealVal以及存储的虚拟部分对_Imagval。第二个构造函数初始化该存储的实部到 _ComplexNum**.real**()以及存储的虚拟部分对 _ComplexNum**.imag**()。

此实现，这样，如果转换器不支持成员模板函数，模板:

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

将替换为:

   complex(const complex& right);

哪些是复制构造函数。

示例

// 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.

要求

标头: <complex>

命名空间: std

请参见

参考

complex Class