// global_search.java   global search minimum 


public class global_search
{

  double f(double x, double y)
  {
    return  Math.exp(Math.sin(60.0*x)) + Math.sin(50.0*Math.exp(y)) +
            Math.sin(70.0*Math.sin(x)) + Math.sin(Math.sin(80.0*y)) -
            Math.sin(20.0*(x+y)) + (x*x+y*y)/4.0;
  }

  public global_search()
  {
    double xmin = -1.0;
    double xmax = 1.0;
    double ymin = -1.0;
    double ymax = 1.0;
    double z;
    double dx = 0.001;
    double dy = 0.001;
    double xbest = 99.0;
    double ybest = 99.0;
    double zbest = 1000.0;
    int pmax = 10;
    int p = 0;
    
    System.out.println("global_search.java running");
    System.out.println("xmin="+xmin+"  xmax="+xmax);
    System.out.println("ymin="+ymin+"  ymax="+ymax);
    System.out.println("dx="+dx+"  dy="+dy);
    
    for(double x=xmin; x<xmax; x=x+dx)
    {
      for(double y=ymin; y<ymax; y=y+dy)
      {
        z = f(x,y);
        if(p<pmax)
	{
	    System.out.println("x="+x+"  y="+y+"  z="+z);
	    p = p+1;
	}
	if(z<zbest)
	{
	  zbest = z;
	  xbest = x;
	  ybest = y;
	}
      } // end y
    } // end x
    System.out.println("xbest="+xbest);
    System.out.println("ybest="+ybest);
    System.out.println("zbest="+zbest);
    System.out.println("dx="+dx+"  dy="+dy);
    System.out.println("global_search.java finished");
  }
    
  public static void main(String[] args)
  {
    new global_search();
  } // end main
} // end class global_search