/* fortran/zhpr.f -- translated by f2c (version 20200916).
   You must link the resulting object file with libf2c:
        on Microsoft Windows system, link with libf2c.lib;
        on Linux or Unix systems, link with .../path/to/libf2c.a -lm
        or, if you install libf2c.a in a standard place, with -lf2c -lm
        -- in that order, at the end of the command line, as in
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        Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,

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*/

#ifdef __cplusplus
extern "C" {
#endif
#include "lmp_f2c.h"

/* > \brief \b ZHPR */

/*  =========== DOCUMENTATION =========== */

/* Online html documentation available at */
/*            http://www.netlib.org/lapack/explore-html/ */

/*  Definition: */
/*  =========== */

/*       SUBROUTINE ZHPR(UPLO,N,ALPHA,X,INCX,AP) */

/*       .. Scalar Arguments .. */
/*       DOUBLE PRECISION ALPHA */
/*       INTEGER INCX,N */
/*       CHARACTER UPLO */
/*       .. */
/*       .. Array Arguments .. */
/*       COMPLEX*16 AP(*),X(*) */
/*       .. */


/* > \par Purpose: */
/*  ============= */
/* > */
/* > \verbatim */
/* > */
/* > ZHPR    performs the hermitian rank 1 operation */
/* > */
/* >    A := alpha*x*x**H + A, */
/* > */
/* > where alpha is a real scalar, x is an n element vector and A is an */
/* > n by n hermitian matrix, supplied in packed form. */
/* > \endverbatim */

/*  Arguments: */
/*  ========== */

/* > \param[in] UPLO */
/* > \verbatim */
/* >          UPLO is CHARACTER*1 */
/* >           On entry, UPLO specifies whether the upper or lower */
/* >           triangular part of the matrix A is supplied in the packed */
/* >           array AP as follows: */
/* > */
/* >              UPLO = 'U' or 'u'   The upper triangular part of A is */
/* >                                  supplied in AP. */
/* > */
/* >              UPLO = 'L' or 'l'   The lower triangular part of A is */
/* >                                  supplied in AP. */
/* > \endverbatim */
/* > */
/* > \param[in] N */
/* > \verbatim */
/* >          N is INTEGER */
/* >           On entry, N specifies the order of the matrix A. */
/* >           N must be at least zero. */
/* > \endverbatim */
/* > */
/* > \param[in] ALPHA */
/* > \verbatim */
/* >          ALPHA is DOUBLE PRECISION. */
/* >           On entry, ALPHA specifies the scalar alpha. */
/* > \endverbatim */
/* > */
/* > \param[in] X */
/* > \verbatim */
/* >          X is COMPLEX*16 array, dimension at least */
/* >           ( 1 + ( n - 1 )*abs( INCX ) ). */
/* >           Before entry, the incremented array X must contain the n */
/* >           element vector x. */
/* > \endverbatim */
/* > */
/* > \param[in] INCX */
/* > \verbatim */
/* >          INCX is INTEGER */
/* >           On entry, INCX specifies the increment for the elements of */
/* >           X. INCX must not be zero. */
/* > \endverbatim */
/* > */
/* > \param[in,out] AP */
/* > \verbatim */
/* >          AP is COMPLEX*16 array, dimension at least */
/* >           ( ( n*( n + 1 ) )/2 ). */
/* >           Before entry with  UPLO = 'U' or 'u', the array AP must */
/* >           contain the upper triangular part of the hermitian matrix */
/* >           packed sequentially, column by column, so that AP( 1 ) */
/* >           contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 ) */
/* >           and a( 2, 2 ) respectively, and so on. On exit, the array */
/* >           AP is overwritten by the upper triangular part of the */
/* >           updated matrix. */
/* >           Before entry with UPLO = 'L' or 'l', the array AP must */
/* >           contain the lower triangular part of the hermitian matrix */
/* >           packed sequentially, column by column, so that AP( 1 ) */
/* >           contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 ) */
/* >           and a( 3, 1 ) respectively, and so on. On exit, the array */
/* >           AP is overwritten by the lower triangular part of the */
/* >           updated matrix. */
/* >           Note that the imaginary parts of the diagonal elements need */
/* >           not be set, they are assumed to be zero, and on exit they */
/* >           are set to zero. */
/* > \endverbatim */

/*  Authors: */
/*  ======== */

/* > \author Univ. of Tennessee */
/* > \author Univ. of California Berkeley */
/* > \author Univ. of Colorado Denver */
/* > \author NAG Ltd. */

/* > \ingroup complex16_blas_level2 */

/* > \par Further Details: */
/*  ===================== */
/* > */
/* > \verbatim */
/* > */
/* >  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. */
/* > \endverbatim */
/* > */
/*  ===================================================================== */
/* Subroutine */ int zhpr_(char *uplo, integer *n, doublereal *alpha,
        doublecomplex *x, integer *incx, doublecomplex *ap, ftnlen uplo_len)
{
    /* System generated locals */
    integer i__1, i__2, i__3, i__4, i__5;
    doublereal d__1;
    doublecomplex z__1, z__2;

    /* Builtin functions */
    void d_lmp_cnjg(doublecomplex *, doublecomplex *);

    /* Local variables */
    integer i__, j, k, kk, ix, jx, kx, info;
    doublecomplex temp;
    extern logical lsame_(char *, char *, ftnlen, ftnlen);
    extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);


/*  -- Reference BLAS level2 routine -- */
/*  -- Reference BLAS is a software package provided by Univ. of Tennessee,    -- */
/*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */

/*     .. Scalar Arguments .. */
/*     .. */
/*     .. Array Arguments .. */
/*     .. */

/*  ===================================================================== */

/*     .. Parameters .. */
/*     .. */
/*     .. Local Scalars .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. External Subroutines .. */
/*     .. */
/*     .. Intrinsic Functions .. */
/*     .. */

/*     Test the input parameters. */

    /* Parameter adjustments */
    --ap;
    --x;

    /* Function Body */
    info = 0;
    if (! lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1) && ! lsame_(uplo, (char *)"L", (
            ftnlen)1, (ftnlen)1)) {
        info = 1;
    } else if (*n < 0) {
        info = 2;
    } else if (*incx == 0) {
        info = 5;
    }
    if (info != 0) {
        xerbla_((char *)"ZHPR  ", &info, (ftnlen)6);
        return 0;
    }

/*     Quick return if possible. */

    if (*n == 0 || *alpha == 0.) {
        return 0;
    }

/*     Set the start point in X if the increment is not unity. */

    if (*incx <= 0) {
        kx = 1 - (*n - 1) * *incx;
    } else if (*incx != 1) {
        kx = 1;
    }

/*     Start the operations. In this version the elements of the array AP */
/*     are accessed sequentially with one pass through AP. */

    kk = 1;
    if (lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1)) {

/*        Form  A  when upper triangle is stored in AP. */

        if (*incx == 1) {
            i__1 = *n;
            for (j = 1; j <= i__1; ++j) {
                i__2 = j;
                if (x[i__2].r != 0. || x[i__2].i != 0.) {
                    d_lmp_cnjg(&z__2, &x[j]);
                    z__1.r = *alpha * z__2.r, z__1.i = *alpha * z__2.i;
                    temp.r = z__1.r, temp.i = z__1.i;
                    k = kk;
                    i__2 = j - 1;
                    for (i__ = 1; i__ <= i__2; ++i__) {
                        i__3 = k;
                        i__4 = k;
                        i__5 = i__;
                        z__2.r = x[i__5].r * temp.r - x[i__5].i * temp.i,
                                z__2.i = x[i__5].r * temp.i + x[i__5].i *
                                temp.r;
                        z__1.r = ap[i__4].r + z__2.r, z__1.i = ap[i__4].i +
                                z__2.i;
                        ap[i__3].r = z__1.r, ap[i__3].i = z__1.i;
                        ++k;
/* L10: */
                    }
                    i__2 = kk + j - 1;
                    i__3 = kk + j - 1;
                    i__4 = j;
                    z__1.r = x[i__4].r * temp.r - x[i__4].i * temp.i, z__1.i =
                             x[i__4].r * temp.i + x[i__4].i * temp.r;
                    d__1 = ap[i__3].r + z__1.r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                } else {
                    i__2 = kk + j - 1;
                    i__3 = kk + j - 1;
                    d__1 = ap[i__3].r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                }
                kk += j;
/* L20: */
            }
        } else {
            jx = kx;
            i__1 = *n;
            for (j = 1; j <= i__1; ++j) {
                i__2 = jx;
                if (x[i__2].r != 0. || x[i__2].i != 0.) {
                    d_lmp_cnjg(&z__2, &x[jx]);
                    z__1.r = *alpha * z__2.r, z__1.i = *alpha * z__2.i;
                    temp.r = z__1.r, temp.i = z__1.i;
                    ix = kx;
                    i__2 = kk + j - 2;
                    for (k = kk; k <= i__2; ++k) {
                        i__3 = k;
                        i__4 = k;
                        i__5 = ix;
                        z__2.r = x[i__5].r * temp.r - x[i__5].i * temp.i,
                                z__2.i = x[i__5].r * temp.i + x[i__5].i *
                                temp.r;
                        z__1.r = ap[i__4].r + z__2.r, z__1.i = ap[i__4].i +
                                z__2.i;
                        ap[i__3].r = z__1.r, ap[i__3].i = z__1.i;
                        ix += *incx;
/* L30: */
                    }
                    i__2 = kk + j - 1;
                    i__3 = kk + j - 1;
                    i__4 = jx;
                    z__1.r = x[i__4].r * temp.r - x[i__4].i * temp.i, z__1.i =
                             x[i__4].r * temp.i + x[i__4].i * temp.r;
                    d__1 = ap[i__3].r + z__1.r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                } else {
                    i__2 = kk + j - 1;
                    i__3 = kk + j - 1;
                    d__1 = ap[i__3].r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                }
                jx += *incx;
                kk += j;
/* L40: */
            }
        }
    } else {

/*        Form  A  when lower triangle is stored in AP. */

        if (*incx == 1) {
            i__1 = *n;
            for (j = 1; j <= i__1; ++j) {
                i__2 = j;
                if (x[i__2].r != 0. || x[i__2].i != 0.) {
                    d_lmp_cnjg(&z__2, &x[j]);
                    z__1.r = *alpha * z__2.r, z__1.i = *alpha * z__2.i;
                    temp.r = z__1.r, temp.i = z__1.i;
                    i__2 = kk;
                    i__3 = kk;
                    i__4 = j;
                    z__1.r = temp.r * x[i__4].r - temp.i * x[i__4].i, z__1.i =
                             temp.r * x[i__4].i + temp.i * x[i__4].r;
                    d__1 = ap[i__3].r + z__1.r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                    k = kk + 1;
                    i__2 = *n;
                    for (i__ = j + 1; i__ <= i__2; ++i__) {
                        i__3 = k;
                        i__4 = k;
                        i__5 = i__;
                        z__2.r = x[i__5].r * temp.r - x[i__5].i * temp.i,
                                z__2.i = x[i__5].r * temp.i + x[i__5].i *
                                temp.r;
                        z__1.r = ap[i__4].r + z__2.r, z__1.i = ap[i__4].i +
                                z__2.i;
                        ap[i__3].r = z__1.r, ap[i__3].i = z__1.i;
                        ++k;
/* L50: */
                    }
                } else {
                    i__2 = kk;
                    i__3 = kk;
                    d__1 = ap[i__3].r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                }
                kk = kk + *n - j + 1;
/* L60: */
            }
        } else {
            jx = kx;
            i__1 = *n;
            for (j = 1; j <= i__1; ++j) {
                i__2 = jx;
                if (x[i__2].r != 0. || x[i__2].i != 0.) {
                    d_lmp_cnjg(&z__2, &x[jx]);
                    z__1.r = *alpha * z__2.r, z__1.i = *alpha * z__2.i;
                    temp.r = z__1.r, temp.i = z__1.i;
                    i__2 = kk;
                    i__3 = kk;
                    i__4 = jx;
                    z__1.r = temp.r * x[i__4].r - temp.i * x[i__4].i, z__1.i =
                             temp.r * x[i__4].i + temp.i * x[i__4].r;
                    d__1 = ap[i__3].r + z__1.r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                    ix = jx;
                    i__2 = kk + *n - j;
                    for (k = kk + 1; k <= i__2; ++k) {
                        ix += *incx;
                        i__3 = k;
                        i__4 = k;
                        i__5 = ix;
                        z__2.r = x[i__5].r * temp.r - x[i__5].i * temp.i,
                                z__2.i = x[i__5].r * temp.i + x[i__5].i *
                                temp.r;
                        z__1.r = ap[i__4].r + z__2.r, z__1.i = ap[i__4].i +
                                z__2.i;
                        ap[i__3].r = z__1.r, ap[i__3].i = z__1.i;
/* L70: */
                    }
                } else {
                    i__2 = kk;
                    i__3 = kk;
                    d__1 = ap[i__3].r;
                    ap[i__2].r = d__1, ap[i__2].i = 0.;
                }
                jx += *incx;
                kk = kk + *n - j + 1;
/* L80: */
            }
        }
    }

    return 0;

/*     End of ZHPR */

} /* zhpr_ */

#ifdef __cplusplus
        }
#endif