norm

Extrait la norme d'un nombre complexe.

template<class Type> 
   Type norm( 
      const complex<Type>& _ComplexNum 
   );

Paramètres

• _ComplexNum
  Le nombre complexe de la norme doit être déterminée.

Valeur de retour

La norme d'un nombre complexe.

Notes

La norme d'un nombre complexe a + BI est (a2 + b)2. La norme d'un nombre complexe est un carré de son modulo. Le modulo d'un nombre complexe est une mesure de la longueur du vecteur qui représente le nombre complexe. Le modulo d'un nombre complexe a + BI est sqrt*(a*2 + b)2, écrit |a + BI|.

Exemple

// complex_norm.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;

   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;

   // The modulus and argument of a complex number can be recovered
   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;
   
   // The norm of a complex number is the square of its modulus
   double normc2 = norm ( c2 );
   double sqrtnormc2 = sqrt ( normc2 );
   cout << "The norm of c2 given by: norm ( c2 ) = " << normc2 << endl;
   cout << "The modulus of c2 is the square root of the norm: "
        << "sqrt ( normc2 ) = " << sqrtnormc2 << "."; 
}

Configuration requise

**En-tête :**complexe <de >

Espace de noms : std