/* static/zlarft.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
                cc *.o -lf2c -lm
        Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,

                http://www.netlib.org/f2c/libf2c.zip
*/

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

/* Table of constant values */

static doublecomplex c_b1 = {1.,0.};
static integer c__1 = 1;

/* > \brief \b ZLARFT forms the triangular factor T of a block reflector H = I - vtvH */

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

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

/* > \htmlonly */
/* > Download ZLARFT + dependencies */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlarft.
f"> */
/* > [TGZ]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlarft.
f"> */
/* > [ZIP]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlarft.
f"> */
/* > [TXT]</a> */
/* > \endhtmlonly */

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

/*       SUBROUTINE ZLARFT( DIRECT, STOREV, N, K, V, LDV, TAU, T, LDT ) */

/*       .. Scalar Arguments .. */
/*       CHARACTER          DIRECT, STOREV */
/*       INTEGER            K, LDT, LDV, N */
/*       .. */
/*       .. Array Arguments .. */
/*       COMPLEX*16         T( LDT, * ), TAU( * ), V( LDV, * ) */
/*       .. */


/* > \par Purpose: */
/*  ============= */
/* > */
/* > \verbatim */
/* > */
/* > ZLARFT forms the triangular factor T of a complex block reflector H */
/* > of order n, which is defined as a product of k elementary reflectors. */
/* > */
/* > If DIRECT = 'F', H = H(1) H(2) . . . H(k) and T is upper triangular; */
/* > */
/* > If DIRECT = 'B', H = H(k) . . . H(2) H(1) and T is lower triangular. */
/* > */
/* > If STOREV = 'C', the vector which defines the elementary reflector */
/* > H(i) is stored in the i-th column of the array V, and */
/* > */
/* >    H  =  I - V * T * V**H */
/* > */
/* > If STOREV = 'R', the vector which defines the elementary reflector */
/* > H(i) is stored in the i-th row of the array V, and */
/* > */
/* >    H  =  I - V**H * T * V */
/* > \endverbatim */

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

/* > \param[in] DIRECT */
/* > \verbatim */
/* >          DIRECT is CHARACTER*1 */
/* >          Specifies the order in which the elementary reflectors are */
/* >          multiplied to form the block reflector: */
/* >          = 'F': H = H(1) H(2) . . . H(k) (Forward) */
/* >          = 'B': H = H(k) . . . H(2) H(1) (Backward) */
/* > \endverbatim */
/* > */
/* > \param[in] STOREV */
/* > \verbatim */
/* >          STOREV is CHARACTER*1 */
/* >          Specifies how the vectors which define the elementary */
/* >          reflectors are stored (see also Further Details): */
/* >          = 'C': columnwise */
/* >          = 'R': rowwise */
/* > \endverbatim */
/* > */
/* > \param[in] N */
/* > \verbatim */
/* >          N is INTEGER */
/* >          The order of the block reflector H. N >= 0. */
/* > \endverbatim */
/* > */
/* > \param[in] K */
/* > \verbatim */
/* >          K is INTEGER */
/* >          The order of the triangular factor T (= the number of */
/* >          elementary reflectors). K >= 1. */
/* > \endverbatim */
/* > */
/* > \param[in] V */
/* > \verbatim */
/* >          V is COMPLEX*16 array, dimension */
/* >                               (LDV,K) if STOREV = 'C' */
/* >                               (LDV,N) if STOREV = 'R' */
/* >          The matrix V. See further details. */
/* > \endverbatim */
/* > */
/* > \param[in] LDV */
/* > \verbatim */
/* >          LDV is INTEGER */
/* >          The leading dimension of the array V. */
/* >          If STOREV = 'C', LDV >= max(1,N); if STOREV = 'R', LDV >= K. */
/* > \endverbatim */
/* > */
/* > \param[in] TAU */
/* > \verbatim */
/* >          TAU is COMPLEX*16 array, dimension (K) */
/* >          TAU(i) must contain the scalar factor of the elementary */
/* >          reflector H(i). */
/* > \endverbatim */
/* > */
/* > \param[out] T */
/* > \verbatim */
/* >          T is COMPLEX*16 array, dimension (LDT,K) */
/* >          The k by k triangular factor T of the block reflector. */
/* >          If DIRECT = 'F', T is upper triangular; if DIRECT = 'B', T is */
/* >          lower triangular. The rest of the array is not used. */
/* > \endverbatim */
/* > */
/* > \param[in] LDT */
/* > \verbatim */
/* >          LDT is INTEGER */
/* >          The leading dimension of the array T. LDT >= K. */
/* > \endverbatim */

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

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

/* > \ingroup complex16OTHERauxiliary */

/* > \par Further Details: */
/*  ===================== */
/* > */
/* > \verbatim */
/* > */
/* >  The shape of the matrix V and the storage of the vectors which define */
/* >  the H(i) is best illustrated by the following example with n = 5 and */
/* >  k = 3. The elements equal to 1 are not stored. */
/* > */
/* >  DIRECT = 'F' and STOREV = 'C':         DIRECT = 'F' and STOREV = 'R': */
/* > */
/* >               V = (  1       )                 V = (  1 v1 v1 v1 v1 ) */
/* >                   ( v1  1    )                     (     1 v2 v2 v2 ) */
/* >                   ( v1 v2  1 )                     (        1 v3 v3 ) */
/* >                   ( v1 v2 v3 ) */
/* >                   ( v1 v2 v3 ) */
/* > */
/* >  DIRECT = 'B' and STOREV = 'C':         DIRECT = 'B' and STOREV = 'R': */
/* > */
/* >               V = ( v1 v2 v3 )                 V = ( v1 v1  1       ) */
/* >                   ( v1 v2 v3 )                     ( v2 v2 v2  1    ) */
/* >                   (  1 v2 v3 )                     ( v3 v3 v3 v3  1 ) */
/* >                   (     1 v3 ) */
/* >                   (        1 ) */
/* > \endverbatim */
/* > */
/*  ===================================================================== */
/* Subroutine */ int zlarft_(char *direct, char *storev, integer *n, integer *
        k, doublecomplex *v, integer *ldv, doublecomplex *tau, doublecomplex *
        t, integer *ldt, ftnlen direct_len, ftnlen storev_len)
{
    /* System generated locals */
    integer t_dim1, t_offset, v_dim1, v_offset, i__1, i__2, i__3, i__4, i__5;
    doublecomplex z__1, z__2, z__3;

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

    /* Local variables */
    integer i__, j, prevlastv;
    extern logical lsame_(char *, char *, ftnlen, ftnlen);
    extern /* Subroutine */ int zgemm_(char *, char *, integer *, integer *,
            integer *, doublecomplex *, doublecomplex *, integer *,
            doublecomplex *, integer *, doublecomplex *, doublecomplex *,
            integer *, ftnlen, ftnlen), zgemv_(char *, integer *, integer *,
            doublecomplex *, doublecomplex *, integer *, doublecomplex *,
            integer *, doublecomplex *, doublecomplex *, integer *, ftnlen);
    integer lastv;
    extern /* Subroutine */ int ztrmv_(char *, char *, char *, integer *,
            doublecomplex *, integer *, doublecomplex *, integer *, ftnlen,
            ftnlen, ftnlen);


/*  -- LAPACK auxiliary routine -- */
/*  -- LAPACK 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 Subroutines .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. Executable Statements .. */

/*     Quick return if possible */

    /* Parameter adjustments */
    v_dim1 = *ldv;
    v_offset = 1 + v_dim1;
    v -= v_offset;
    --tau;
    t_dim1 = *ldt;
    t_offset = 1 + t_dim1;
    t -= t_offset;

    /* Function Body */
    if (*n == 0) {
        return 0;
    }

    if (lsame_(direct, (char *)"F", (ftnlen)1, (ftnlen)1)) {
        prevlastv = *n;
        i__1 = *k;
        for (i__ = 1; i__ <= i__1; ++i__) {
            prevlastv = max(prevlastv,i__);
            i__2 = i__;
            if (tau[i__2].r == 0. && tau[i__2].i == 0.) {

/*              H(i)  =  I */

                i__2 = i__;
                for (j = 1; j <= i__2; ++j) {
                    i__3 = j + i__ * t_dim1;
                    t[i__3].r = 0., t[i__3].i = 0.;
                }
            } else {

/*              general case */

                if (lsame_(storev, (char *)"C", (ftnlen)1, (ftnlen)1)) {
/*                 Skip any trailing zeros. */
                    i__2 = i__ + 1;
                    for (lastv = *n; lastv >= i__2; --lastv) {
                        i__3 = lastv + i__ * v_dim1;
                        if (v[i__3].r != 0. || v[i__3].i != 0.) {
                            goto L220;
                        }
                    }
L220:
                    i__2 = i__ - 1;
                    for (j = 1; j <= i__2; ++j) {
                        i__3 = j + i__ * t_dim1;
                        i__4 = i__;
                        z__2.r = -tau[i__4].r, z__2.i = -tau[i__4].i;
                        d_cnjg(&z__3, &v[i__ + j * v_dim1]);
                        z__1.r = z__2.r * z__3.r - z__2.i * z__3.i, z__1.i =
                                z__2.r * z__3.i + z__2.i * z__3.r;
                        t[i__3].r = z__1.r, t[i__3].i = z__1.i;
                    }
                    j = min(lastv,prevlastv);

/*                 T(1:i-1,i) := - tau(i) * V(i:j,1:i-1)**H * V(i:j,i) */

                    i__2 = j - i__;
                    i__3 = i__ - 1;
                    i__4 = i__;
                    z__1.r = -tau[i__4].r, z__1.i = -tau[i__4].i;
                    zgemv_((char *)"Conjugate transpose", &i__2, &i__3, &z__1, &v[i__
                            + 1 + v_dim1], ldv, &v[i__ + 1 + i__ * v_dim1], &
                            c__1, &c_b1, &t[i__ * t_dim1 + 1], &c__1, (ftnlen)
                            19);
                } else {
/*                 Skip any trailing zeros. */
                    i__2 = i__ + 1;
                    for (lastv = *n; lastv >= i__2; --lastv) {
                        i__3 = i__ + lastv * v_dim1;
                        if (v[i__3].r != 0. || v[i__3].i != 0.) {
                            goto L236;
                        }
                    }
L236:
                    i__2 = i__ - 1;
                    for (j = 1; j <= i__2; ++j) {
                        i__3 = j + i__ * t_dim1;
                        i__4 = i__;
                        z__2.r = -tau[i__4].r, z__2.i = -tau[i__4].i;
                        i__5 = j + i__ * v_dim1;
                        z__1.r = z__2.r * v[i__5].r - z__2.i * v[i__5].i,
                                z__1.i = z__2.r * v[i__5].i + z__2.i * v[i__5]
                                .r;
                        t[i__3].r = z__1.r, t[i__3].i = z__1.i;
                    }
                    j = min(lastv,prevlastv);

/*                 T(1:i-1,i) := - tau(i) * V(1:i-1,i:j) * V(i,i:j)**H */

                    i__2 = i__ - 1;
                    i__3 = j - i__;
                    i__4 = i__;
                    z__1.r = -tau[i__4].r, z__1.i = -tau[i__4].i;
                    zgemm_((char *)"N", (char *)"C", &i__2, &c__1, &i__3, &z__1, &v[(i__ + 1)
                            * v_dim1 + 1], ldv, &v[i__ + (i__ + 1) * v_dim1],
                            ldv, &c_b1, &t[i__ * t_dim1 + 1], ldt, (ftnlen)1,
                            (ftnlen)1);
                }

/*              T(1:i-1,i) := T(1:i-1,1:i-1) * T(1:i-1,i) */

                i__2 = i__ - 1;
                ztrmv_((char *)"Upper", (char *)"No transpose", (char *)"Non-unit", &i__2, &t[
                        t_offset], ldt, &t[i__ * t_dim1 + 1], &c__1, (ftnlen)
                        5, (ftnlen)12, (ftnlen)8);
                i__2 = i__ + i__ * t_dim1;
                i__3 = i__;
                t[i__2].r = tau[i__3].r, t[i__2].i = tau[i__3].i;
                if (i__ > 1) {
                    prevlastv = max(prevlastv,lastv);
                } else {
                    prevlastv = lastv;
                }
            }
        }
    } else {
        prevlastv = 1;
        for (i__ = *k; i__ >= 1; --i__) {
            i__1 = i__;
            if (tau[i__1].r == 0. && tau[i__1].i == 0.) {

/*              H(i)  =  I */

                i__1 = *k;
                for (j = i__; j <= i__1; ++j) {
                    i__2 = j + i__ * t_dim1;
                    t[i__2].r = 0., t[i__2].i = 0.;
                }
            } else {

/*              general case */

                if (i__ < *k) {
                    if (lsame_(storev, (char *)"C", (ftnlen)1, (ftnlen)1)) {
/*                    Skip any leading zeros. */
                        i__1 = i__ - 1;
                        for (lastv = 1; lastv <= i__1; ++lastv) {
                            i__2 = lastv + i__ * v_dim1;
                            if (v[i__2].r != 0. || v[i__2].i != 0.) {
                                goto L281;
                            }
                        }
L281:
                        i__1 = *k;
                        for (j = i__ + 1; j <= i__1; ++j) {
                            i__2 = j + i__ * t_dim1;
                            i__3 = i__;
                            z__2.r = -tau[i__3].r, z__2.i = -tau[i__3].i;
                            d_cnjg(&z__3, &v[*n - *k + i__ + j * v_dim1]);
                            z__1.r = z__2.r * z__3.r - z__2.i * z__3.i,
                                    z__1.i = z__2.r * z__3.i + z__2.i *
                                    z__3.r;
                            t[i__2].r = z__1.r, t[i__2].i = z__1.i;
                        }
                        j = max(lastv,prevlastv);

/*                    T(i+1:k,i) = -tau(i) * V(j:n-k+i,i+1:k)**H * V(j:n-k+i,i) */

                        i__1 = *n - *k + i__ - j;
                        i__2 = *k - i__;
                        i__3 = i__;
                        z__1.r = -tau[i__3].r, z__1.i = -tau[i__3].i;
                        zgemv_((char *)"Conjugate transpose", &i__1, &i__2, &z__1, &v[
                                j + (i__ + 1) * v_dim1], ldv, &v[j + i__ *
                                v_dim1], &c__1, &c_b1, &t[i__ + 1 + i__ *
                                t_dim1], &c__1, (ftnlen)19);
                    } else {
/*                    Skip any leading zeros. */
                        i__1 = i__ - 1;
                        for (lastv = 1; lastv <= i__1; ++lastv) {
                            i__2 = i__ + lastv * v_dim1;
                            if (v[i__2].r != 0. || v[i__2].i != 0.) {
                                goto L297;
                            }
                        }
L297:
                        i__1 = *k;
                        for (j = i__ + 1; j <= i__1; ++j) {
                            i__2 = j + i__ * t_dim1;
                            i__3 = i__;
                            z__2.r = -tau[i__3].r, z__2.i = -tau[i__3].i;
                            i__4 = j + (*n - *k + i__) * v_dim1;
                            z__1.r = z__2.r * v[i__4].r - z__2.i * v[i__4].i,
                                    z__1.i = z__2.r * v[i__4].i + z__2.i * v[
                                    i__4].r;
                            t[i__2].r = z__1.r, t[i__2].i = z__1.i;
                        }
                        j = max(lastv,prevlastv);

/*                    T(i+1:k,i) = -tau(i) * V(i+1:k,j:n-k+i) * V(i,j:n-k+i)**H */

                        i__1 = *k - i__;
                        i__2 = *n - *k + i__ - j;
                        i__3 = i__;
                        z__1.r = -tau[i__3].r, z__1.i = -tau[i__3].i;
                        zgemm_((char *)"N", (char *)"C", &i__1, &c__1, &i__2, &z__1, &v[i__ +
                                1 + j * v_dim1], ldv, &v[i__ + j * v_dim1],
                                ldv, &c_b1, &t[i__ + 1 + i__ * t_dim1], ldt, (
                                ftnlen)1, (ftnlen)1);
                    }

/*                 T(i+1:k,i) := T(i+1:k,i+1:k) * T(i+1:k,i) */

                    i__1 = *k - i__;
                    ztrmv_((char *)"Lower", (char *)"No transpose", (char *)"Non-unit", &i__1, &t[i__
                            + 1 + (i__ + 1) * t_dim1], ldt, &t[i__ + 1 + i__ *
                             t_dim1], &c__1, (ftnlen)5, (ftnlen)12, (ftnlen)8)
                            ;
                    if (i__ > 1) {
                        prevlastv = min(prevlastv,lastv);
                    } else {
                        prevlastv = lastv;
                    }
                }
                i__1 = i__ + i__ * t_dim1;
                i__2 = i__;
                t[i__1].r = tau[i__2].r, t[i__1].i = tau[i__2].i;
            }
        }
    }
    return 0;

/*     End of ZLARFT */

} /* zlarft_ */

#ifdef __cplusplus
        }
#endif