# dlib C++ Library - cblas_zhbmv.c

    /*
     * cblas_zhbmv.c
     * The program is a C interface to zhbmv
     *
     * Keita Teranishi  5/18/98
     *
     */
    #include "cblas.h"
    #include "cblas_f77.h"
    #include <stdio.h>
    #include <stdlib.h>
    void cblas_zhbmv(const enum CBLAS_ORDER order,
                     const enum CBLAS_UPLO Uplo,const CBLAS_INT_TYPE N,const CBLAS_INT_TYPE K,
                     const void *alpha, const void  *A, const CBLAS_INT_TYPE lda,
                     const void  *X, const CBLAS_INT_TYPE incX, const void *beta,
                     void  *Y, const CBLAS_INT_TYPE incY)
    {
       char UL;
    #ifdef F77_CHAR
       F77_CHAR F77_UL;
    #else
       #define F77_UL &UL
    #endif
    #ifdef F77_INT
       F77_INT F77_N=N, F77_K=K, F77_lda=lda, F77_incX=incX, F77_incY=incY;
    #else
       #define F77_N N
       #define F77_K K
       #define F77_lda lda
       #define F77_incX incx
       #define F77_incY incY
    #endif
       CBLAS_INT_TYPE n, i=0, incx=incX;
       const double *xx= (double *)X, *alp= (double *)alpha, *bet = (double *)beta;
       double ALPHA[2],BETA[2];
       CBLAS_INT_TYPE tincY, tincx;
       double *x=(double *)X, *y=(double *)Y, *st=0, *tx;

       if (order == CblasColMajor)
       {
          if (Uplo == CblasLower) UL = 'L';
          else if (Uplo == CblasUpper) UL = 'U';
          else
          {
             cblas_xerbla(2, "cblas_zhbmv","Illegal Uplo setting, %d\n",Uplo );
             return;
          }
          #ifdef F77_CHAR
             F77_UL = C2F_CHAR(&UL);
          #endif
          F77_zhbmv(F77_UL, &F77_N, &F77_K, alpha, A, &F77_lda, X,
                         &F77_incX, beta, Y, &F77_incY);
       }
       else if (order == CblasRowMajor)
       {
          ALPHA[0]= *alp;
          ALPHA[1]= -alp[1];
          BETA[0]= *bet;
          BETA[1]= -bet[1];

          if (N > 0)
          {
             n = N << 1;
             x = malloc(n*sizeof(double));

             tx = x;
             if( incX > 0 ) {
               i = incX << 1 ;
               tincx = 2;
               st= x+n;
             } else {
               i = incX *(-2);
               tincx = -2;
               st = x-2;
               x +=(n-2);
             }

             do
             {
               *x = *xx;
               x[1] = -xx[1];
               x += tincx ;
               xx += i;
             }
             while (x != st);
             x=tx;

             #ifdef F77_INT
                F77_incX = 1;
             #else
                incx = 1;
             #endif

             if(incY > 0)
               tincY = incY;
             else
               tincY = -incY;
             y++;

             i = tincY << 1;
             n = i * N ;
             st = y + n;
             do {
                *y = -(*y);
                y += i;
             } while(y != st);
             y -= n;
          }  else
             x = (double *) X;

          if (Uplo == CblasUpper) UL = 'L';
          else if (Uplo == CblasLower) UL = 'U';
          else
          {
             cblas_xerbla(2, "cblas_zhbmv","Illegal Uplo setting, %d\n", Uplo);
             return;
          }
          #ifdef F77_CHAR
             F77_UL = C2F_CHAR(&UL);
          #endif
          F77_zhbmv(F77_UL, &F77_N, &F77_K, ALPHA,
                         A ,&F77_lda, x,&F77_incX, BETA, Y, &F77_incY);
       }
       else
       {
          cblas_xerbla(1, "cblas_zhbmv","Illegal Order setting, %d\n", order);
          return;
       }
       if ( order == CblasRowMajor )
       {
          if(X!=x)
             free(x);
          if (N > 0)
          {
             do
             {
                *y = -(*y);
                y += i;
             }
             while (y != st);
          }
       }
       return;
    }