//		vectors.cc
#include <math.h>
#include <iostream.h>

double fu(const int i)
{
  double t1     = 1.0/(i+1);
  return ( t1*t1 );
}

double fw(const int n, const int i)
{
  return ( sin(4.0*M_PI*(i-1.0)/(n-1.0)) );
}


double InnerProd( const int n, const double x[], const double y[] )
{
  int    i;
  double sum = 0.0;

  for ( i=0; i<n; i++)
  {
    sum += x[i] * y[i];
  }

  return (sum);
}

double EuklidNorm( const int n, const double x[] )
{
  return ( sqrt( InnerProd(n,x,x) ) );
}

void Calc_z(const int n, double z[], const double alpha, const double beta,
		   const double x[], const double y[])
{
 int i;
 for ( i=0; i<n; i++ )
   {
     z[2*i]   =         x[i] + beta * y[i];
     z[2*i+1] = alpha * x[i] +        y[i];
   }
  return;
}


void Print(const int n, const double z[])
{
 int i;

 cout << endl << "  Datenausgabe z" << endl << endl;
 if ( n<=40 )
   {
     for ( i=0; i<n; i++)
       {
         cout << i << " : " << z[i] << endl;
       }
   }
 else
   {
     cout << 0   << " : " << z[0]   << endl;
     cout << 1   << " : " << z[1]   << endl;
     cout << n-2 << " : " << z[n-2] << endl;
     cout << n-1 << " : " << z[n-1] << endl;
   }
 cout << endl;
 return;
}