#include "blaswrap.h"
#include "f2c.h"

/* Subroutine */ int chbmv_(char *uplo, integer *n, integer *k, complex *
	alpha, complex *a, integer *lda, complex *x, integer *incx, complex *
	beta, complex *y, integer *incy)
{
    /* System generated locals */
    integer a_dim1, a_offset, i__1, i__2, i__3, i__4, i__5;
    real r__1;
    complex q__1, q__2, q__3, q__4;
    /* Builtin functions */
    void r_cnjg(complex *, complex *);
    /* Local variables */
    static integer info;
    static complex temp1, temp2;
    static integer i__, j, l;
    extern logical lsame_(char *, char *);
    static integer kplus1, ix, iy, jx, jy, kx, ky;
    extern /* Subroutine */ int xerbla_(char *, integer *);
#define a_subscr(a_1,a_2) (a_2)*a_dim1 + a_1
#define a_ref(a_1,a_2) a[a_subscr(a_1,a_2)]
/*  Purpose   
    =======   
    CHBMV  performs the matrix-vector  operation   
       y := alpha*A*x + beta*y,   
    where alpha and beta are scalars, x and y are n element vectors and   
    A is an n by n hermitian band matrix, with k super-diagonals.   
    Parameters   
    ==========   
    UPLO   - CHARACTER*1.   
             On entry, UPLO specifies whether the upper or lower   
             triangular part of the band matrix A is being supplied as   
             follows:   
                UPLO = 'U' or 'u'   The upper triangular part of A is   
                                    being supplied.   
                UPLO = 'L' or 'l'   The lower triangular part of A is   
                                    being supplied.   
             Unchanged on exit.   
    N      - INTEGER.   
             On entry, N specifies the order of the matrix A.   
             N must be at least zero.   
             Unchanged on exit.   
    K      - INTEGER.   
             On entry, K specifies the number of super-diagonals of the   
             matrix A. K must satisfy  0 .le. K.   
             Unchanged on exit.   
    ALPHA  - COMPLEX         .   
             On entry, ALPHA specifies the scalar alpha.   
             Unchanged on exit.   
    A      - COMPLEX          array of DIMENSION ( LDA, n ).   
             Before entry with UPLO = 'U' or 'u', the leading ( k + 1 )   
             by n part of the array A must contain the upper triangular   
             band part of the hermitian matrix, supplied column by   
             column, with the leading diagonal of the matrix in row   
             ( k + 1 ) of the array, the first super-diagonal starting at   
             position 2 in row k, and so on. The top left k by k triangle   
             of the array A is not referenced.   
             The following program segment will transfer the upper   
             triangular part of a hermitian band matrix from conventional   
             full matrix storage to band storage:   
                   DO 20, J = 1, N   
                      M = K + 1 - J   
                      DO 10, I = MAX( 1, J - K ), J   
                         A( M + I, J ) = matrix( I, J )   
                10    CONTINUE   
                20 CONTINUE   
             Before entry with UPLO = 'L' or 'l', the leading ( k + 1 )   
             by n part of the array A must contain the lower triangular   
             band part of the hermitian matrix, supplied column by   
             column, with the leading diagonal of the matrix in row 1 of   
             the array, the first sub-diagonal starting at position 1 in   
             row 2, and so on. The bottom right k by k triangle of the   
             array A is not referenced.   
             The following program segment will transfer the lower   
             triangular part of a hermitian band matrix from conventional   
             full matrix storage to band storage:   
                   DO 20, J = 1, N   
                      M = 1 - J   
                      DO 10, I = J, MIN( N, J + K )   
                         A( M + I, J ) = matrix( I, J )   
                10    CONTINUE   
                20 CONTINUE   
             Note that the imaginary parts of the diagonal elements need   
             not be set and are assumed to be zero.   
             Unchanged on exit.   
    LDA    - INTEGER.   
             On entry, LDA specifies the first dimension of A as declared   
             in the calling (sub) program. LDA must be at least   
             ( k + 1 ).   
             Unchanged on exit.   
    X      - COMPLEX          array of DIMENSION at least   
             ( 1 + ( n - 1 )*abs( INCX ) ).   
             Before entry, the incremented array X must contain the   
             vector x.   
             Unchanged on exit.   
    INCX   - INTEGER.   
             On entry, INCX specifies the increment for the elements of   
             X. INCX must not be zero.   
             Unchanged on exit.   
    BETA   - COMPLEX         .   
             On entry, BETA specifies the scalar beta.   
             Unchanged on exit.   
    Y      - COMPLEX          array of DIMENSION at least   
             ( 1 + ( n - 1 )*abs( INCY ) ).   
             Before entry, the incremented array Y must contain the   
             vector y. On exit, Y is overwritten by the updated vector y.   
    INCY   - INTEGER.   
             On entry, INCY specifies the increment for the elements of   
             Y. INCY must not be zero.   
             Unchanged on exit.   
    Level 2 Blas routine.   
    -- Written on 22-October-1986.   
       Jack Dongarra, Argonne National Lab.   
       Jeremy Du Croz, Nag Central Office.   
       Sven Hammarling, Nag Central Office.   
       Richard Hanson, Sandia National Labs.   
       Test the input parameters.   
       Parameter adjustments */
    a_dim1 = *lda;
    a_offset = 1 + a_dim1 * 1;
    a -= a_offset;
    --x;
    --y;
    /* Function Body */
    info = 0;
    if (! lsame_(uplo, "U") && ! lsame_(uplo, "L")) {
	info = 1;
    } else if (*n < 0) {
	info = 2;
    } else if (*k < 0) {
	info = 3;
    } else if (*lda < *k + 1) {
	info = 6;
    } else if (*incx == 0) {
	info = 8;
    } else if (*incy == 0) {
	info = 11;
    }
    if (info != 0) {
	xerbla_("CHBMV ", &info);
	return 0;
    }
/*     Quick return if possible. */
    if (*n == 0 || alpha->r == 0.f && alpha->i == 0.f && (beta->r == 1.f && 
	    beta->i == 0.f)) {
	return 0;
    }
/*     Set up the start points in  X  and  Y. */
    if (*incx > 0) {
	kx = 1;
    } else {
	kx = 1 - (*n - 1) * *incx;
    }
    if (*incy > 0) {
	ky = 1;
    } else {
	ky = 1 - (*n - 1) * *incy;
    }
/*     Start the operations. In this version the elements of the array A   
       are accessed sequentially with one pass through A.   
       First form  y := beta*y. */
    if (beta->r != 1.f || beta->i != 0.f) {
	if (*incy == 1) {
	    if (beta->r == 0.f && beta->i == 0.f) {
		i__1 = *n;
		for (i__ = 1; i__ <= i__1; ++i__) {
		    i__2 = i__;
		    y[i__2].r = 0.f, y[i__2].i = 0.f;
/* L10: */
		}
	    } else {
		i__1 = *n;
		for (i__ = 1; i__ <= i__1; ++i__) {
		    i__2 = i__;
		    i__3 = i__;
		    q__1.r = beta->r * y[i__3].r - beta->i * y[i__3].i, 
			    q__1.i = beta->r * y[i__3].i + beta->i * y[i__3]
			    .r;
		    y[i__2].r = q__1.r, y[i__2].i = q__1.i;
/* L20: */
		}
	    }
	} else {
	    iy = ky;
	    if (beta->r == 0.f && beta->i == 0.f) {
		i__1 = *n;
		for (i__ = 1; i__ <= i__1; ++i__) {
		    i__2 = iy;
		    y[i__2].r = 0.f, y[i__2].i = 0.f;
		    iy += *incy;
/* L30: */
		}
	    } else {
		i__1 = *n;
		for (i__ = 1; i__ <= i__1; ++i__) {
		    i__2 = iy;
		    i__3 = iy;
		    q__1.r = beta->r * y[i__3].r - beta->i * y[i__3].i, 
			    q__1.i = beta->r * y[i__3].i + beta->i * y[i__3]
			    .r;
		    y[i__2].r = q__1.r, y[i__2].i = q__1.i;
		    iy += *incy;
/* L40: */
		}
	    }
	}
    }
    if (alpha->r == 0.f && alpha->i == 0.f) {
	return 0;
    }
    if (lsame_(uplo, "U")) {
/*        Form  y  when upper triangle of A is stored. */
	kplus1 = *k + 1;
	if (*incx == 1 && *incy == 1) {
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
		i__2 = j;
		q__1.r = alpha->r * x[i__2].r - alpha->i * x[i__2].i, q__1.i =
			 alpha->r * x[i__2].i + alpha->i * x[i__2].r;
		temp1.r = q__1.r, temp1.i = q__1.i;
		temp2.r = 0.f, temp2.i = 0.f;
		l = kplus1 - j;
/* Computing MAX */
		i__2 = 1, i__3 = j - *k;
		i__4 = j - 1;
		for (i__ = max(i__2,i__3); i__ <= i__4; ++i__) {
		    i__2 = i__;
		    i__3 = i__;
		    i__5 = a_subscr(l + i__, j);
		    q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, 
			    q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5]
			    .r;
		    q__1.r = y[i__3].r + q__2.r, q__1.i = y[i__3].i + q__2.i;
		    y[i__2].r = q__1.r, y[i__2].i = q__1.i;
		    r_cnjg(&q__3, &a_ref(l + i__, j));
		    i__2 = i__;
		    q__2.r = q__3.r * x[i__2].r - q__3.i * x[i__2].i, q__2.i =
			     q__3.r * x[i__2].i + q__3.i * x[i__2].r;
		    q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i;
		    temp2.r = q__1.r, temp2.i = q__1.i;
/* L50: */
		}
		i__4 = j;
		i__2 = j;
		i__3 = a_subscr(kplus1, j);
		r__1 = a[i__3].r;
		q__3.r = r__1 * temp1.r, q__3.i = r__1 * temp1.i;
		q__2.r = y[i__2].r + q__3.r, q__2.i = y[i__2].i + q__3.i;
		q__4.r = alpha->r * temp2.r - alpha->i * temp2.i, q__4.i = 
			alpha->r * temp2.i + alpha->i * temp2.r;
		q__1.r = q__2.r + q__4.r, q__1.i = q__2.i + q__4.i;
		y[i__4].r = q__1.r, y[i__4].i = q__1.i;
/* L60: */
	    }
	} else {
	    jx = kx;
	    jy = ky;
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
		i__4 = jx;
		q__1.r = alpha->r * x[i__4].r - alpha->i * x[i__4].i, q__1.i =
			 alpha->r * x[i__4].i + alpha->i * x[i__4].r;
		temp1.r = q__1.r, temp1.i = q__1.i;
		temp2.r = 0.f, temp2.i = 0.f;
		ix = kx;
		iy = ky;
		l = kplus1 - j;
/* Computing MAX */
		i__4 = 1, i__2 = j - *k;
		i__3 = j - 1;
		for (i__ = max(i__4,i__2); i__ <= i__3; ++i__) {
		    i__4 = iy;
		    i__2 = iy;
		    i__5 = a_subscr(l + i__, j);
		    q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, 
			    q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5]
			    .r;
		    q__1.r = y[i__2].r + q__2.r, q__1.i = y[i__2].i + q__2.i;
		    y[i__4].r = q__1.r, y[i__4].i = q__1.i;
		    r_cnjg(&q__3, &a_ref(l + i__, j));
		    i__4 = ix;
		    q__2.r = q__3.r * x[i__4].r - q__3.i * x[i__4].i, q__2.i =
			     q__3.r * x[i__4].i + q__3.i * x[i__4].r;
		    q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i;
		    temp2.r = q__1.r, temp2.i = q__1.i;
		    ix += *incx;
		    iy += *incy;
/* L70: */
		}
		i__3 = jy;
		i__4 = jy;
		i__2 = a_subscr(kplus1, j);
		r__1 = a[i__2].r;
		q__3.r = r__1 * temp1.r, q__3.i = r__1 * temp1.i;
		q__2.r = y[i__4].r + q__3.r, q__2.i = y[i__4].i + q__3.i;
		q__4.r = alpha->r * temp2.r - alpha->i * temp2.i, q__4.i = 
			alpha->r * temp2.i + alpha->i * temp2.r;
		q__1.r = q__2.r + q__4.r, q__1.i = q__2.i + q__4.i;
		y[i__3].r = q__1.r, y[i__3].i = q__1.i;
		jx += *incx;
		jy += *incy;
		if (j > *k) {
		    kx += *incx;
		    ky += *incy;
		}
/* L80: */
	    }
	}
    } else {
/*        Form  y  when lower triangle of A is stored. */
	if (*incx == 1 && *incy == 1) {
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
		i__3 = j;
		q__1.r = alpha->r * x[i__3].r - alpha->i * x[i__3].i, q__1.i =
			 alpha->r * x[i__3].i + alpha->i * x[i__3].r;
		temp1.r = q__1.r, temp1.i = q__1.i;
		temp2.r = 0.f, temp2.i = 0.f;
		i__3 = j;
		i__4 = j;
		i__2 = a_subscr(1, j);
		r__1 = a[i__2].r;
		q__2.r = r__1 * temp1.r, q__2.i = r__1 * temp1.i;
		q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i;
		y[i__3].r = q__1.r, y[i__3].i = q__1.i;
		l = 1 - j;
/* Computing MIN */
		i__4 = *n, i__2 = j + *k;
		i__3 = min(i__4,i__2);
		for (i__ = j + 1; i__ <= i__3; ++i__) {
		    i__4 = i__;
		    i__2 = i__;
		    i__5 = a_subscr(l + i__, j);
		    q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, 
			    q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5]
			    .r;
		    q__1.r = y[i__2].r + q__2.r, q__1.i = y[i__2].i + q__2.i;
		    y[i__4].r = q__1.r, y[i__4].i = q__1.i;
		    r_cnjg(&q__3, &a_ref(l + i__, j));
		    i__4 = i__;
		    q__2.r = q__3.r * x[i__4].r - q__3.i * x[i__4].i, q__2.i =
			     q__3.r * x[i__4].i + q__3.i * x[i__4].r;
		    q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i;
		    temp2.r = q__1.r, temp2.i = q__1.i;
/* L90: */
		}
		i__3 = j;
		i__4 = j;
		q__2.r = alpha->r * temp2.r - alpha->i * temp2.i, q__2.i = 
			alpha->r * temp2.i + alpha->i * temp2.r;
		q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i;
		y[i__3].r = q__1.r, y[i__3].i = q__1.i;
/* L100: */
	    }
	} else {
	    jx = kx;
	    jy = ky;
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
		i__3 = jx;
		q__1.r = alpha->r * x[i__3].r - alpha->i * x[i__3].i, q__1.i =
			 alpha->r * x[i__3].i + alpha->i * x[i__3].r;
		temp1.r = q__1.r, temp1.i = q__1.i;
		temp2.r = 0.f, temp2.i = 0.f;
		i__3 = jy;
		i__4 = jy;
		i__2 = a_subscr(1, j);
		r__1 = a[i__2].r;
		q__2.r = r__1 * temp1.r, q__2.i = r__1 * temp1.i;
		q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i;
		y[i__3].r = q__1.r, y[i__3].i = q__1.i;
		l = 1 - j;
		ix = jx;
		iy = jy;
/* Computing MIN */
		i__4 = *n, i__2 = j + *k;
		i__3 = min(i__4,i__2);
		for (i__ = j + 1; i__ <= i__3; ++i__) {
		    ix += *incx;
		    iy += *incy;
		    i__4 = iy;
		    i__2 = iy;
		    i__5 = a_subscr(l + i__, j);
		    q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, 
			    q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5]
			    .r;
		    q__1.r = y[i__2].r + q__2.r, q__1.i = y[i__2].i + q__2.i;
		    y[i__4].r = q__1.r, y[i__4].i = q__1.i;
		    r_cnjg(&q__3, &a_ref(l + i__, j));
		    i__4 = ix;
		    q__2.r = q__3.r * x[i__4].r - q__3.i * x[i__4].i, q__2.i =
			     q__3.r * x[i__4].i + q__3.i * x[i__4].r;
		    q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i;
		    temp2.r = q__1.r, temp2.i = q__1.i;
/* L110: */
		}
		i__3 = jy;
		i__4 = jy;
		q__2.r = alpha->r * temp2.r - alpha->i * temp2.i, q__2.i = 
			alpha->r * temp2.i + alpha->i * temp2.r;
		q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i;
		y[i__3].r = q__1.r, y[i__3].i = q__1.i;
		jx += *incx;
		jy += *incy;
/* L120: */
	    }
	}
    }
    return 0;
/*     End of CHBMV . */
} /* chbmv_ */
#undef a_ref
#undef a_subscr

