    /*
     * cblas_zhpr2.c
     * The program is a C interface to zhpr2.
     *
     * Keita Teranishi  5/20/98
     *
     */
    #include <stdio.h>
    #include <stdlib.h>
    #include "cblas.h"
    #include "cblas_f77.h"
    void cblas_zhpr2(const enum CBLAS_ORDER order, const enum CBLAS_UPLO Uplo,
                          const int N,const void *alpha, const void *X,
                          const int incX,const void *Y, const int incY, void *Ap)

    {
       char UL;
    #ifdef F77_CHAR
       F77_CHAR F77_UL;
    #else
       #define F77_UL &UL
    #endif

    #ifdef F77_INT
       F77_INT F77_N=N,  F77_incX=incX, F77_incY=incY;
    #else
       #define F77_N N
       #define F77_incX incx
       #define F77_incY incy
    #endif
       int n, i, j, incx=incX, incy=incY;
       double *x=(double *)X, *xx=(double *)X, *y=(double *)Y,
             *yy=(double *)Y, *stx, *sty;

       if (order == CblasColMajor)
       {
          if (Uplo == CblasLower) UL = 'L';
          else if (Uplo == CblasUpper) UL = 'U';
          else
          {
             cblas_xerbla(2, "cblas_zhpr2","Illegal Uplo setting, %d\n",Uplo );
             return;
          }
          #ifdef F77_CHAR
             F77_UL = C2F_CHAR(&UL);
          #endif

          F77_zhpr2(F77_UL, &F77_N, alpha, X, &F77_incX, Y, &F77_incY, Ap);

       }  else if (order == CblasRowMajor)
       {
          if (Uplo == CblasUpper) UL = 'L';
          else if (Uplo == CblasLower) UL = 'U';
          else
          {
             cblas_xerbla(2, "cblas_zhpr2","Illegal Uplo setting, %d\n", Uplo);
             return;
          }
          #ifdef F77_CHAR
             F77_UL = C2F_CHAR(&UL);
          #endif
          if (N > 0)
          {
             n = N << 1;
             x = malloc(n*sizeof(double));
             y = malloc(n*sizeof(double));
             stx = x + n;
             sty = y + n;
             if( incX > 0 )
                i = incX << 1;
             else
                i = incX *(-2);

             if( incY > 0 )
                j = incY << 1;
             else
                j = incY *(-2);
             do
             {
                *x = *xx;
                x[1] = -xx[1];
                x += 2;
                xx += i;
             } while (x != stx);
             do
             {
                *y = *yy;
                y[1] = -yy[1];
                y += 2;
                yy += j;
             }
             while (y != sty);
             x -= n;
             y -= n;

             #ifdef F77_INT
                if(incX > 0 )
                   F77_incX = 1;
                else
                   F77_incX = -1;

                if(incY > 0 )
                   F77_incY = 1;
                else
                   F77_incY = -1;

             #else
                if(incX > 0 )
                   incx = 1;
                else
                   incx = -1;

                if(incY > 0 )
                   incy = 1;
                else
                   incy = -1;
             #endif

          }  else
          {
             x = (double *) X;
             y = (void  *) Y;
          }
          F77_zhpr2(F77_UL, &F77_N, alpha, y, &F77_incY, x, &F77_incX, Ap);
       }
       else
       {
          cblas_xerbla(1, "cblas_zhpr2","Illegal Order setting, %d\n", order);
          return;
       }
       if(X!=x)
          free(x);
       if(Y!=y)
          free(y);
       return;
    }