www.pudn.com > cghost.rar > ATRDE.C

 
  #include "math.h" 
  #include "stdio.h" 
  int atrde(b,n,m,d) 
  int n,m; 
  double b[],d[]; 
  { int k,j; 
    double s; 
    if (m!=(3*n-2)) 
      { printf("err\n"); return(-2);} 
    for (k=0;k<=n-2;k++) 
      { j=3*k; s=b[j]; 
        if (fabs(s)+1.0==1.0) 
          { printf("fail\n"); return(0);} 
        b[j+1]=b[j+1]/s; 
        d[k]=d[k]/s; 
        b[j+3]=b[j+3]-b[j+2]*b[j+1]; 
        d[k+1]=d[k+1]-b[j+2]*d[k]; 
      } 
    s=b[3*n-3]; 
    if (fabs(s)+1.0==1.0) 
      { printf("fail\n"); return(0);} 
    d[n-1]=d[n-1]/s; 
    for (k=n-2;k>=0;k--) 
      d[k]=d[k]-b[3*k+1]*d[k+1]; 
    return(2); 
  }