arg
複合型の引数を展開します。
template<class Type>
Type arg(
const complex<Type>& _ComplexNum
);
パラメーター
- _ComplexNum
引数が決定される複素数。
戻り値
複素数の引数。
解説
引数は、複雑なベクターが複雑な平面の正の実際の軸に対する角度です。複雑なのは + Bi は、引数 arctan と同じです (b/a) *。*測定されたときに測定すると、時計回り方向に負の角度に正の実際の軸から反時計回りでは正の意味があります。主な値は –pi 大きく未満で、または +pi になります。
使用例
// complex_arg.cpp
// compile with: /EHsc
#include <complex>
#include <iostream>
int main( )
{
using namespace std;
double pi = 3.14159265359;
// Complex numbers can be entered in polar form with
// modulus and argument parameter inputs but are
// stored in Cartesian form as real & imag coordinates
complex <double> c1 ( polar ( 5.0 ) ); // Default argument = 0
complex <double> c2 ( polar ( 5.0 , pi / 6 ) );
complex <double> c3 ( polar ( 5.0 , 13 * pi / 6 ) );
cout << "c1 = polar ( 5.0 ) = " << c1 << endl;
cout << "c2 = polar ( 5.0 , pi / 6 ) = " << c2 << endl;
cout << "c3 = polar ( 5.0 , 13 * pi / 6 ) = " << c3 << endl;
// The modulus and argument of a complex number can be rcovered
// using abs & arg member functions
double absc1 = abs ( c1 );
double argc1 = arg ( c1 );
cout << "The modulus of c1 is recovered from c1 using: abs ( c1 ) = "
<< absc1 << endl;
cout << "Argument of c1 is recovered from c1 using:\n arg ( c1 ) = "
<< argc1 << " radians, which is " << argc1 * 180 / pi
<< " degrees." << endl;
double absc2 = abs ( c2 );
double argc2 = arg ( c2 );
cout << "The modulus of c2 is recovered from c2 using: abs ( c2 ) = "
<< absc2 << endl;
cout << "Argument of c2 is recovered from c2 using:\n arg ( c2 ) = "
<< argc2 << " radians, which is " << argc2 * 180 / pi
<< " degrees." << endl;
// Testing if the principal angles of c2 and c3 are the same
if ( (arg ( c2 ) <= ( arg ( c3 ) + .00000001) ) ||
(arg ( c2 ) >= ( arg ( c3 ) - .00000001) ) )
cout << "The complex numbers c2 & c3 have the "
<< "same principal arguments."<< endl;
else
cout << "The complex numbers c2 & c3 don't have the "
<< "same principal arguments." << endl;
}
必要条件
ヘッダー: <complex>
名前空間: std