cubicsplineinterpolation.java

数值计算（科学计算）实验代码高斯消元楚列斯基分解

public class CubicSplineInterpolation {
 public double CubicSplineInterpolation(double[] t,double[] y,double m)
 {
	double yValue=0;
	double[][] aaaa=this.arrary(t);
	Gaussian b=new Gaussian();
	double[] value=new double[8];
		value[0]=y[0];
		value[1]=y[1];
		value[2]=y[1];
		value[3]=y[2];
	for(int i=4;i<8;i++)
		value[i]=0;
	//double[] value=new double[8];
	value=b.Gaussian(aaaa, value, 8);
	if(m>=t[0]&&m<=t[1]) {yValue=value[0]+value[1]*m+value[2]*m*m+value[3]*m*m;
	return yValue;  
	}
	else if(m>t[1]&&m<=t[2]){yValue=value[4]+value[5]*m+value[6]*m*m+value[7]*m*m;
	return yValue;  
	}
	else return 0;
	//return yValue; 
 }
public double[][] arrary (double[] t)
{
double[][] arrary=new double[8][8];	
for(int i=0;i<8;i++)
	for(int j=0;j<8;j++)
		arrary[i][j]=0;

//1-2
    arrary[0][0]=1;
    arrary[1][0]=1;
    for(int i=0;i<=1;i++)
    	for(int j=1;j<=3;j++)
    		arrary[i][j]=arrary[i][j-1]*t[i];
//3-4
    arrary[2][4]=1;
    arrary[3][4]=1;
    for(int i=2;i<=3;i++)
    	for(int j=5;j<=7;j++)
    		arrary[i][j]=arrary[i][j-1]*t[i-1];  
 //5   
    arrary[4][1]=1;
    arrary[4][2]=2*t[1];
    arrary[4][3]=3*t[1]*t[1];
    arrary[4][5]=-1;
    arrary[4][6]=-2*t[1];
    arrary[4][7]=-3*t[1]*t[1];
    
  //6  
    arrary[5][2]=2;
    arrary[5][3]=6*t[1];
    arrary[5][6]=-2;
    arrary[5][7]=-6*t[1];
//7
    arrary[6][2]=2;
    arrary[6][3]=6*t[0];   
//8
    arrary[7][6]=2;
    arrary[7][7]=6*t[2];  
    for(int i=0;i<8;i++)
    	{for(int j=0;j<8;j++)
    		System.out.print(arrary[i][j]+"\t");
    	System.out.println();
    	}
return arrary;
}
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
}