Различные алгоритмы минимизации, реализованные в С++ / all / PARTAN2

#include <conio.h>
#include <iostream.h>
#include <math.h>

struct Vector
{
 double x1,x2;
 Vector()
 {
  x1=0;
  x2=0;
 }
 Vector(double ax1,double ax2)
 {
  x1=ax1;
  x2=ax2;
 }
 const Vector operator * (const double &vec) const
 {
  return Vector(x1*vec,x2*vec);
 }

 const void operator = (const Vector &vec)
 {
  x1=vec.x1;
  x2=vec.x2;
 }

 const double operator * (const Vector &vec) const
 {
  return (x1*vec.x1+x2*vec.x2);
 }

 const Vector operator + (const Vector &vec) const
 {
  return Vector(x1+vec.x1,x2+vec.x2);
 }

 const Vector operator - (const Vector &vec) const
 {
  return Vector(x1-vec.x1,x2-vec.x2);
 }
};

double function(Vector vec)
{
// return (4*(vec.x1-5)*(vec.x1-5)+(vec.x2-6)*(vec.x2-6));
// return(8*vec.x1*vec.x1+4*vec.x1*vec.x2+5*vec.x2*vec.x2);
 return((vec.x2-vec.x1*vec.x1)*(vec.x2-vec.x1*vec.x1)+100*(1-vec.x1)*(1-vec.x1));
}

double f_dx1(Vector vec)
{
// return (8*(vec.x1-5));
// return(16*vec.x1+4*vec.x2);
 return(-4*(vec.x2-vec.x1*vec.x1)*vec.x1-200*(1-vec.x1));
}

double f_dx2(Vector vec)
{
// return (2*(vec.x2-6));
// return(4*vec.x1+10*vec.x2);
 return(2*(vec.x2-vec.x1*vec.x1));
}

Vector Angrad(Vector vec)
{
 Vector grad;
 grad=Vector(f_dx1(vec),f_dx2(vec));
 return (grad*(-1));
}

double proizv(Vector vec,Vector p)
{
 Vector grad;
 grad=Vector(f_dx1(vec),f_dx2(vec));
 return (grad*p);
}

void Swann4(Vector &x1,double &a,double &b,Vector &p)
{
 double pr;
 Vector x2;
 pr=proizv(x1,p);
 if(pr>0) p=Vector(0,0)-p;
 b=fabs(function(x1)/pr-1);
 if(b>1) b=1;
 x2=x1+p*b;
 while(proizv(x1,p)*proizv(x2,p)>0)
 {
  a=b;
  b*=2;
  x1=x2;
  x2=x1+p*b;
 }
}

double Alfa(Vector &x1,Vector p,double a1,double b1)
{
 double e=0.0001,w,z,ar,k;
 Vector r;
 Swann4(x1,a1,b1,p);
 z=proizv(x1+p*a1,p)+proizv(x1+p*b1,p)+3*(function(x1+p*a1)-function(x1+p*b1))/(b1-a1);
 w=sqrt(z*z-proizv(x1+p*a1,p)*proizv(x1+p*b1,p));
 ar=b1*(w-proizv(x1+p*a1,p)+z)/(2*w-proizv(x1+p*a1,p)+proizv(x1+p*b1,p));
 return(ar);
}

void Partan(Vector &x1)
{
 Vector x2,x3,x4,d,p;
 double e=0.00001,a,n,a1,b1;
 do
 {
  p=Angrad(x1);
  a=Alfa(x1,p,a1,b1);
  x2=x1+p*a;
  p=Angrad(x2);
  a=Alfa(x2,p,a1,b1);
  x3=x2+p*a;
  d=x3-x1;
  a=Alfa(x3,d,a1,b1);
  x4=x3+d*a;
  x1=x2;
  n=sqrt(d.x1*d.x1+d.x2*d.x2);
 }while(n>e);
 cout<<x4.x1<<endl<<x4.x2;
}

void main()
{
 clrscr();
 Vector x1;
 double a1=0,b1=0;
 x1=Vector(1,2);
 Partan(x1);
 getch();
}