三次样条插值C语言程序

//文件名：splineinsert.cpp 
/************************************************************************* 
* 
*   函数名称： 
*       splineinsert() 
* 
*   参数: 
*   InContourSide                 -   存储内轮廓的节点链表 
*   返回值: 
*       BOOL                               -   运算成功返回TRUE，否则返回FALSE。 
* 
*   说明: 
*   该函数用于输出提取出的轮廓数据。 
*   
*   要求轮廓图象已经过扫描，建立起轮廓图象，对轮廓数据进行三次样条插值。 
************************************************************************/ 

//通过此函数调用三次样条插值 
BOOL   WINAPI   splineinsert(ChainHead*     InContourSide,ChainHead*   ReplaceSide) 
{ 
int   i,j,k; 
int   direction; 
int   LongSize; 
int   TotalSize,other; 
ChainHead*     pChain; 
Node*               pNode   =   NULL;   
Node*               mNode   =   NULL; 
Node*               sNode   =   NULL; 
Node*               BreakNode   =   NULL; 

int                   MidFlag; 
Node*               MinNode   =   NULL; 
        Node*               MaxNode   =   NULL; 
//边界条件,即假定边界为切矢无穷大 
double     yp1   =   1.7E30; 
double     ypn   =   1.7E30; 

/* 
此处代码省,目的是把轮廓分成上下两条 
因为样条插值要求沿一个方向是增大/减小的 
*/ 

//x,y   是输入的坐标值   n是数据点的个数   
//yp1,ypn是端始点的二阶导数值   y2为输出的二阶导数值 
spline(Xb,   Yb,   k,   yp1,   ypn,   y2); 

LongSize   =   (int)(MaxNode-> x-MinNode-> x)+1;     //插值点的个数 
double*         sig   =   new   double[LongSize]; 
double*         xcha   =   new   double[LongSize]; 

xcha[0]   =   Xb[0]; 
for(i=1;   i <LongSize;   i++) 
{ 
xcha[i]   =   xcha[i-1]+1; 
} 

for(i=0;   i <=LongSize;   i++) 
{ 
splint(Xb,   Yb,   y2,   k,   xcha[i],   sig[i]); 
}