int
f2c_zher2(char* uplo, integer* N,
doublecomplex* alpha,
doublecomplex* X, integer* incX,
doublecomplex* Y, integer* incY,
doublecomplex* A, integer* lda)
{
zher2_(uplo, N, alpha,
X, incX, Y, incY, A, lda);
return 0;
}
void cblas_zher2(const enum CBLAS_ORDER order, const enum CBLAS_UPLO Uplo,
const integer N, const void *alpha, const void *X, const integer incX,
const void *Y, const integer incY, void *A, const integer lda)
{
char UL;
#ifdef F77_CHAR
F77_CHAR F77_UL;
#else
#define F77_UL &UL
#endif
#define F77_N N
#define F77_lda lda
#define F77_incX incx
#define F77_incY incy
integer n, i, j, tincx, tincy, incx=incX, incy=incY;
double *x=(double *)X, *xx=(double *)X, *y=(double *)Y,
*yy=(double *)Y, *tx, *ty, *stx, *sty;
extern integer CBLAS_CallFromC;
extern integer RowMajorStrg;
RowMajorStrg = 0;
CBLAS_CallFromC = 1;
if (order == CblasColMajor)
{
if (Uplo == CblasLower) UL = 'L';
else if (Uplo == CblasUpper) UL = 'U';
else
{
cblas_xerbla(2, "cblas_zher2", "Illegal Uplo setting, %d\n",Uplo );
CBLAS_CallFromC = 0;
RowMajorStrg = 0;
return;
}
#ifdef F77_CHAR
F77_UL = C2F_CHAR(&UL);
#endif
zher2_(F77_UL, &F77_N, alpha, X, &F77_incX,
Y, &F77_incY, A, &F77_lda);
} else if (order == CblasRowMajor)
{
RowMajorStrg = 1;
if (Uplo == CblasUpper) UL = 'L';
else if (Uplo == CblasLower) UL = 'U';
else
{
cblas_xerbla(2, "cblas_zher2", "Illegal Uplo setting, %d\n", Uplo);
CBLAS_CallFromC = 0;
RowMajorStrg = 0;
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));
tx = x;
ty = y;
if( incX > 0 ) {
i = incX << 1 ;
tincx = 2;
stx= x+n;
} else {
i = incX *(-2);
tincx = -2;
stx = x-2;
x +=(n-2);
}
if( incY > 0 ) {
j = incY << 1;
tincy = 2;
sty= y+n;
} else {
j = incY *(-2);
tincy = -2;
sty = y-2;
y +=(n-2);
}
do
{
*x = *xx;
x[1] = -xx[1];
x += tincx ;
xx += i;
}
while (x != stx);
do
{
*y = *yy;
y[1] = -yy[1];
y += tincy ;
yy += j;
}
while (y != sty);
x=tx;
y=ty;
incx = 1;
incy = 1;
} else
{
x = (double *) X;
y = (double *) Y;
}
zher2_(F77_UL, &F77_N, alpha, y, &F77_incY, x,
&F77_incX, A, &F77_lda);
}
else
{
cblas_xerbla(1, "cblas_zher2", "Illegal Order setting, %d\n", order);
CBLAS_CallFromC = 0;
RowMajorStrg = 0;
return;
}
if(X!=x)
free(x);
if(Y!=y)
free(y);
CBLAS_CallFromC = 0;
RowMajorStrg = 0;
return;
}
void
zher2(char uplo, int n, doublecomplex *alpha, doublecomplex *x, int incx, doublecomplex *y, int incy, doublecomplex *a, int lda)
{
zher2_( &uplo, &n, alpha, x, &incx, y, &incy, a, &lda);
}
/* Subroutine */ int zlaghe_(integer *n, integer *k, doublereal *d,
doublecomplex *a, integer *lda, integer *iseed, doublecomplex *work,
integer *info)
{
/* System generated locals */
integer a_dim1, a_offset, i__1, i__2, i__3;
doublereal d__1;
doublecomplex z__1, z__2, z__3, z__4;
/* Builtin functions */
double z_abs(doublecomplex *);
void z_div(doublecomplex *, doublecomplex *, doublecomplex *), d_cnjg(
doublecomplex *, doublecomplex *);
/* Local variables */
extern /* Subroutine */ int zher2_(char *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
static integer i, j;
static doublecomplex alpha;
extern /* Subroutine */ int zgerc_(integer *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *), zscal_(integer *, doublecomplex *,
doublecomplex *, integer *);
extern /* Double Complex */ VOID zdotc_(doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *);
extern /* Subroutine */ int zgemv_(char *, integer *, integer *,
doublecomplex *, doublecomplex *, integer *, doublecomplex *,
integer *, doublecomplex *, doublecomplex *, integer *),
zhemv_(char *, integer *, doublecomplex *, doublecomplex *,
integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *), zaxpy_(integer *,
doublecomplex *, doublecomplex *, integer *, doublecomplex *,
integer *);
extern doublereal dznrm2_(integer *, doublecomplex *, integer *);
static doublecomplex wa, wb;
static doublereal wn;
extern /* Subroutine */ int xerbla_(char *, integer *), zlarnv_(
integer *, integer *, integer *, doublecomplex *);
static doublecomplex tau;
/* -- LAPACK auxiliary test routine (version 2.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
September 30, 1994
Purpose
=======
ZLAGHE generates a complex hermitian matrix A, by pre- and post-
multiplying a real diagonal matrix D with a random unitary matrix:
A = U*D*U'. The semi-bandwidth may then be reduced to k by additional
unitary transformations.
Arguments
=========
N (input) INTEGER
The order of the matrix A. N >= 0.
K (input) INTEGER
The number of nonzero subdiagonals within the band of A.
0 <= K <= N-1.
D (input) DOUBLE PRECISION array, dimension (N)
The diagonal elements of the diagonal matrix D.
A (output) COMPLEX*16 array, dimension (LDA,N)
The generated n by n hermitian matrix A (the full matrix is
stored).
LDA (input) INTEGER
The leading dimension of the array A. LDA >= N.
ISEED (input/output) INTEGER array, dimension (4)
On entry, the seed of the random number generator; the array
elements must be between 0 and 4095, and ISEED(4) must be
odd.
On exit, the seed is updated.
WORK (workspace) COMPLEX*16 array, dimension (2*N)
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
=====================================================================
Test the input arguments
Parameter adjustments */
--d;
a_dim1 = *lda;
a_offset = a_dim1 + 1;
a -= a_offset;
--iseed;
--work;
/* Function Body */
*info = 0;
if (*n < 0) {
*info = -1;
} else if (*k < 0 || *k > *n - 1) {
*info = -2;
} else if (*lda < max(1,*n)) {
*info = -5;
}
if (*info < 0) {
i__1 = -(*info);
xerbla_("ZLAGHE", &i__1);
return 0;
}
/* initialize lower triangle of A to diagonal matrix */
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i = j + 1; i <= i__2; ++i) {
i__3 = i + j * a_dim1;
a[i__3].r = 0., a[i__3].i = 0.;
/* L10: */
}
/* L20: */
}
i__1 = *n;
for (i = 1; i <= i__1; ++i) {
i__2 = i + i * a_dim1;
i__3 = i;
a[i__2].r = d[i__3], a[i__2].i = 0.;
/* L30: */
}
/* Generate lower triangle of hermitian matrix */
for (i = *n - 1; i >= 1; --i) {
/* generate random reflection */
i__1 = *n - i + 1;
zlarnv_(&c__3, &iseed[1], &i__1, &work[1]);
i__1 = *n - i + 1;
wn = dznrm2_(&i__1, &work[1], &c__1);
d__1 = wn / z_abs(&work[1]);
z__1.r = d__1 * work[1].r, z__1.i = d__1 * work[1].i;
wa.r = z__1.r, wa.i = z__1.i;
if (wn == 0.) {
tau.r = 0., tau.i = 0.;
} else {
z__1.r = work[1].r + wa.r, z__1.i = work[1].i + wa.i;
wb.r = z__1.r, wb.i = z__1.i;
i__1 = *n - i;
z_div(&z__1, &c_b2, &wb);
zscal_(&i__1, &z__1, &work[2], &c__1);
work[1].r = 1., work[1].i = 0.;
z_div(&z__1, &wb, &wa);
d__1 = z__1.r;
tau.r = d__1, tau.i = 0.;
}
/* apply random reflection to A(i:n,i:n) from the left
and the right
compute y := tau * A * u */
i__1 = *n - i + 1;
zhemv_("Lower", &i__1, &tau, &a[i + i * a_dim1], lda, &work[1], &c__1,
&c_b1, &work[*n + 1], &c__1);
/* compute v := y - 1/2 * tau * ( y, u ) * u */
z__3.r = -.5, z__3.i = 0.;
z__2.r = z__3.r * tau.r - z__3.i * tau.i, z__2.i = z__3.r * tau.i +
z__3.i * tau.r;
i__1 = *n - i + 1;
zdotc_(&z__4, &i__1, &work[*n + 1], &c__1, &work[1], &c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r * z__4.i
+ z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
i__1 = *n - i + 1;
zaxpy_(&i__1, &alpha, &work[1], &c__1, &work[*n + 1], &c__1);
/* apply the transformation as a rank-2 update to A(i:n,i:n) */
i__1 = *n - i + 1;
z__1.r = -1., z__1.i = 0.;
zher2_("Lower", &i__1, &z__1, &work[1], &c__1, &work[*n + 1], &c__1, &
a[i + i * a_dim1], lda);
/* L40: */
}
/* Reduce number of subdiagonals to K */
i__1 = *n - 1 - *k;
for (i = 1; i <= i__1; ++i) {
/* generate reflection to annihilate A(k+i+1:n,i) */
i__2 = *n - *k - i + 1;
wn = dznrm2_(&i__2, &a[*k + i + i * a_dim1], &c__1);
d__1 = wn / z_abs(&a[*k + i + i * a_dim1]);
i__2 = *k + i + i * a_dim1;
z__1.r = d__1 * a[i__2].r, z__1.i = d__1 * a[i__2].i;
wa.r = z__1.r, wa.i = z__1.i;
if (wn == 0.) {
tau.r = 0., tau.i = 0.;
} else {
i__2 = *k + i + i * a_dim1;
z__1.r = a[i__2].r + wa.r, z__1.i = a[i__2].i + wa.i;
wb.r = z__1.r, wb.i = z__1.i;
i__2 = *n - *k - i;
z_div(&z__1, &c_b2, &wb);
zscal_(&i__2, &z__1, &a[*k + i + 1 + i * a_dim1], &c__1);
i__2 = *k + i + i * a_dim1;
a[i__2].r = 1., a[i__2].i = 0.;
z_div(&z__1, &wb, &wa);
d__1 = z__1.r;
tau.r = d__1, tau.i = 0.;
}
/* apply reflection to A(k+i:n,i+1:k+i-1) from the left */
i__2 = *n - *k - i + 1;
i__3 = *k - 1;
zgemv_("Conjugate transpose", &i__2, &i__3, &c_b2, &a[*k + i + (i + 1)
* a_dim1], lda, &a[*k + i + i * a_dim1], &c__1, &c_b1, &work[
1], &c__1);
i__2 = *n - *k - i + 1;
i__3 = *k - 1;
z__1.r = -tau.r, z__1.i = -tau.i;
zgerc_(&i__2, &i__3, &z__1, &a[*k + i + i * a_dim1], &c__1, &work[1],
&c__1, &a[*k + i + (i + 1) * a_dim1], lda);
/* apply reflection to A(k+i:n,k+i:n) from the left and the rig
ht
compute y := tau * A * u */
i__2 = *n - *k - i + 1;
zhemv_("Lower", &i__2, &tau, &a[*k + i + (*k + i) * a_dim1], lda, &a[*
k + i + i * a_dim1], &c__1, &c_b1, &work[1], &c__1);
/* compute v := y - 1/2 * tau * ( y, u ) * u */
z__3.r = -.5, z__3.i = 0.;
z__2.r = z__3.r * tau.r - z__3.i * tau.i, z__2.i = z__3.r * tau.i +
z__3.i * tau.r;
i__2 = *n - *k - i + 1;
zdotc_(&z__4, &i__2, &work[1], &c__1, &a[*k + i + i * a_dim1], &c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r * z__4.i
+ z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
i__2 = *n - *k - i + 1;
zaxpy_(&i__2, &alpha, &a[*k + i + i * a_dim1], &c__1, &work[1], &c__1)
;
/* apply hermitian rank-2 update to A(k+i:n,k+i:n) */
i__2 = *n - *k - i + 1;
z__1.r = -1., z__1.i = 0.;
zher2_("Lower", &i__2, &z__1, &a[*k + i + i * a_dim1], &c__1, &work[1]
, &c__1, &a[*k + i + (*k + i) * a_dim1], lda);
i__2 = *k + i + i * a_dim1;
z__1.r = -wa.r, z__1.i = -wa.i;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
i__2 = *n;
for (j = *k + i + 1; j <= i__2; ++j) {
i__3 = j + i * a_dim1;
a[i__3].r = 0., a[i__3].i = 0.;
/* L50: */
}
/* L60: */
}
/* Store full hermitian matrix */
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i = j + 1; i <= i__2; ++i) {
i__3 = j + i * a_dim1;
d_cnjg(&z__1, &a[i + j * a_dim1]);
a[i__3].r = z__1.r, a[i__3].i = z__1.i;
/* L70: */
}
/* L80: */
}
return 0;
/* End of ZLAGHE */
} /* zlaghe_ */
/* Subroutine */ int zlaghe_(integer *n, integer *k, doublereal *d__,
doublecomplex *a, integer *lda, integer *iseed, doublecomplex *work,
integer *info)
{
/* System generated locals */
integer a_dim1, a_offset, i__1, i__2, i__3;
doublereal d__1;
doublecomplex z__1, z__2, z__3, z__4;
/* Local variables */
integer i__, j;
doublecomplex wa, wb;
doublereal wn;
doublecomplex tau;
doublecomplex alpha;
/* -- LAPACK auxiliary test routine (version 3.1) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZLAGHE generates a complex hermitian matrix A, by pre- and post- */
/* multiplying a real diagonal matrix D with a random unitary matrix: */
/* A = U*D*U'. The semi-bandwidth may then be reduced to k by additional */
/* unitary transformations. */
/* Arguments */
/* ========= */
/* N (input) INTEGER */
/* The order of the matrix A. N >= 0. */
/* K (input) INTEGER */
/* The number of nonzero subdiagonals within the band of A. */
/* 0 <= K <= N-1. */
/* D (input) DOUBLE PRECISION array, dimension (N) */
/* The diagonal elements of the diagonal matrix D. */
/* A (output) COMPLEX*16 array, dimension (LDA,N) */
/* The generated n by n hermitian matrix A (the full matrix is */
/* stored). */
/* LDA (input) INTEGER */
/* The leading dimension of the array A. LDA >= N. */
/* ISEED (input/output) INTEGER array, dimension (4) */
/* On entry, the seed of the random number generator; the array */
/* elements must be between 0 and 4095, and ISEED(4) must be */
/* odd. */
/* On exit, the seed is updated. */
/* WORK (workspace) COMPLEX*16 array, dimension (2*N) */
/* INFO (output) INTEGER */
/* = 0: successful exit */
/* < 0: if INFO = -i, the i-th argument had an illegal value */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Test the input arguments */
/* Parameter adjustments */
--d__;
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
--iseed;
--work;
/* Function Body */
*info = 0;
if (*n < 0) {
*info = -1;
} else if (*k < 0 || *k > *n - 1) {
*info = -2;
} else if (*lda < max(1,*n)) {
*info = -5;
}
if (*info < 0) {
i__1 = -(*info);
xerbla_("ZLAGHE", &i__1);
return 0;
}
/* initialize lower triangle of A to diagonal matrix */
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i__ = j + 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * a_dim1;
a[i__3].r = 0., a[i__3].i = 0.;
/* L10: */
}
/* L20: */
}
i__1 = *n;
for (i__ = 1; i__ <= i__1; ++i__) {
i__2 = i__ + i__ * a_dim1;
i__3 = i__;
a[i__2].r = d__[i__3], a[i__2].i = 0.;
/* L30: */
}
/* Generate lower triangle of hermitian matrix */
for (i__ = *n - 1; i__ >= 1; --i__) {
/* generate random reflection */
i__1 = *n - i__ + 1;
zlarnv_(&c__3, &iseed[1], &i__1, &work[1]);
i__1 = *n - i__ + 1;
wn = dznrm2_(&i__1, &work[1], &c__1);
d__1 = wn / z_abs(&work[1]);
z__1.r = d__1 * work[1].r, z__1.i = d__1 * work[1].i;
wa.r = z__1.r, wa.i = z__1.i;
if (wn == 0.) {
tau.r = 0., tau.i = 0.;
} else {
z__1.r = work[1].r + wa.r, z__1.i = work[1].i + wa.i;
wb.r = z__1.r, wb.i = z__1.i;
i__1 = *n - i__;
z_div(&z__1, &c_b2, &wb);
zscal_(&i__1, &z__1, &work[2], &c__1);
work[1].r = 1., work[1].i = 0.;
z_div(&z__1, &wb, &wa);
d__1 = z__1.r;
tau.r = d__1, tau.i = 0.;
}
/* apply random reflection to A(i:n,i:n) from the left */
/* and the right */
/* compute y := tau * A * u */
i__1 = *n - i__ + 1;
zhemv_("Lower", &i__1, &tau, &a[i__ + i__ * a_dim1], lda, &work[1], &
c__1, &c_b1, &work[*n + 1], &c__1);
/* compute v := y - 1/2 * tau * ( y, u ) * u */
z__3.r = -.5, z__3.i = -0.;
z__2.r = z__3.r * tau.r - z__3.i * tau.i, z__2.i = z__3.r * tau.i +
z__3.i * tau.r;
i__1 = *n - i__ + 1;
zdotc_(&z__4, &i__1, &work[*n + 1], &c__1, &work[1], &c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r * z__4.i
+ z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
i__1 = *n - i__ + 1;
zaxpy_(&i__1, &alpha, &work[1], &c__1, &work[*n + 1], &c__1);
/* apply the transformation as a rank-2 update to A(i:n,i:n) */
i__1 = *n - i__ + 1;
z__1.r = -1., z__1.i = -0.;
zher2_("Lower", &i__1, &z__1, &work[1], &c__1, &work[*n + 1], &c__1, &
a[i__ + i__ * a_dim1], lda);
/* L40: */
}
/* Reduce number of subdiagonals to K */
i__1 = *n - 1 - *k;
for (i__ = 1; i__ <= i__1; ++i__) {
/* generate reflection to annihilate A(k+i+1:n,i) */
i__2 = *n - *k - i__ + 1;
wn = dznrm2_(&i__2, &a[*k + i__ + i__ * a_dim1], &c__1);
d__1 = wn / z_abs(&a[*k + i__ + i__ * a_dim1]);
i__2 = *k + i__ + i__ * a_dim1;
z__1.r = d__1 * a[i__2].r, z__1.i = d__1 * a[i__2].i;
wa.r = z__1.r, wa.i = z__1.i;
if (wn == 0.) {
tau.r = 0., tau.i = 0.;
} else {
i__2 = *k + i__ + i__ * a_dim1;
z__1.r = a[i__2].r + wa.r, z__1.i = a[i__2].i + wa.i;
wb.r = z__1.r, wb.i = z__1.i;
i__2 = *n - *k - i__;
z_div(&z__1, &c_b2, &wb);
zscal_(&i__2, &z__1, &a[*k + i__ + 1 + i__ * a_dim1], &c__1);
i__2 = *k + i__ + i__ * a_dim1;
a[i__2].r = 1., a[i__2].i = 0.;
z_div(&z__1, &wb, &wa);
d__1 = z__1.r;
tau.r = d__1, tau.i = 0.;
}
/* apply reflection to A(k+i:n,i+1:k+i-1) from the left */
i__2 = *n - *k - i__ + 1;
i__3 = *k - 1;
zgemv_("Conjugate transpose", &i__2, &i__3, &c_b2, &a[*k + i__ + (i__
+ 1) * a_dim1], lda, &a[*k + i__ + i__ * a_dim1], &c__1, &
c_b1, &work[1], &c__1);
i__2 = *n - *k - i__ + 1;
i__3 = *k - 1;
z__1.r = -tau.r, z__1.i = -tau.i;
zgerc_(&i__2, &i__3, &z__1, &a[*k + i__ + i__ * a_dim1], &c__1, &work[
1], &c__1, &a[*k + i__ + (i__ + 1) * a_dim1], lda);
/* apply reflection to A(k+i:n,k+i:n) from the left and the right */
/* compute y := tau * A * u */
i__2 = *n - *k - i__ + 1;
zhemv_("Lower", &i__2, &tau, &a[*k + i__ + (*k + i__) * a_dim1], lda,
&a[*k + i__ + i__ * a_dim1], &c__1, &c_b1, &work[1], &c__1);
/* compute v := y - 1/2 * tau * ( y, u ) * u */
z__3.r = -.5, z__3.i = -0.;
z__2.r = z__3.r * tau.r - z__3.i * tau.i, z__2.i = z__3.r * tau.i +
z__3.i * tau.r;
i__2 = *n - *k - i__ + 1;
zdotc_(&z__4, &i__2, &work[1], &c__1, &a[*k + i__ + i__ * a_dim1], &
c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r * z__4.i
+ z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
i__2 = *n - *k - i__ + 1;
zaxpy_(&i__2, &alpha, &a[*k + i__ + i__ * a_dim1], &c__1, &work[1], &
c__1);
/* apply hermitian rank-2 update to A(k+i:n,k+i:n) */
i__2 = *n - *k - i__ + 1;
z__1.r = -1., z__1.i = -0.;
zher2_("Lower", &i__2, &z__1, &a[*k + i__ + i__ * a_dim1], &c__1, &
work[1], &c__1, &a[*k + i__ + (*k + i__) * a_dim1], lda);
i__2 = *k + i__ + i__ * a_dim1;
z__1.r = -wa.r, z__1.i = -wa.i;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
i__2 = *n;
for (j = *k + i__ + 1; j <= i__2; ++j) {
i__3 = j + i__ * a_dim1;
a[i__3].r = 0., a[i__3].i = 0.;
/* L50: */
}
/* L60: */
}
/* Store full hermitian matrix */
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i__ = j + 1; i__ <= i__2; ++i__) {
i__3 = j + i__ * a_dim1;
d_cnjg(&z__1, &a[i__ + j * a_dim1]);
a[i__3].r = z__1.r, a[i__3].i = z__1.i;
/* L70: */
}
/* L80: */
}
return 0;
/* End of ZLAGHE */
} /* zlaghe_ */
/* Subroutine */ int zhegs2_(integer *itype, char *uplo, integer *n,
doublecomplex *a, integer *lda, doublecomplex *b, integer *ldb,
integer *info)
{
/* System generated locals */
integer a_dim1, a_offset, b_dim1, b_offset, i__1, i__2;
doublereal d__1, d__2;
doublecomplex z__1;
/* Local variables */
integer k;
doublecomplex ct;
doublereal akk, bkk;
logical upper;
/* -- LAPACK routine (version 3.2) -- */
/* November 2006 */
/* Purpose */
/* ======= */
/* ZHEGS2 reduces a complex Hermitian-definite generalized */
/* eigenproblem to standard form. */
/* If ITYPE = 1, the problem is A*x = lambda*B*x, */
/* and A is overwritten by inv(U')*A*inv(U) or inv(L)*A*inv(L') */
/* If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or */
/* B*A*x = lambda*x, and A is overwritten by U*A*U` or L'*A*L. */
/* B must have been previously factorized as U'*U or L*L' by ZPOTRF. */
/* Arguments */
/* ========= */
/* ITYPE (input) INTEGER */
/* = 1: compute inv(U')*A*inv(U) or inv(L)*A*inv(L'); */
/* = 2 or 3: compute U*A*U' or L'*A*L. */
/* UPLO (input) CHARACTER*1 */
/* Specifies whether the upper or lower triangular part of the */
/* Hermitian matrix A is stored, and how B has been factorized. */
/* = 'U': Upper triangular */
/* = 'L': Lower triangular */
/* N (input) INTEGER */
/* The order of the matrices A and B. N >= 0. */
/* A (input/output) COMPLEX*16 array, dimension (LDA,N) */
/* On entry, the Hermitian matrix A. If UPLO = 'U', the leading */
/* n by n upper triangular part of A contains the upper */
/* triangular part of the matrix A, and the strictly lower */
/* triangular part of A is not referenced. If UPLO = 'L', the */
/* leading n by n lower triangular part of A contains the lower */
/* triangular part of the matrix A, and the strictly upper */
/* triangular part of A is not referenced. */
/* On exit, if INFO = 0, the transformed matrix, stored in the */
/* same format as A. */
/* LDA (input) INTEGER */
/* The leading dimension of the array A. LDA >= max(1,N). */
/* B (input) COMPLEX*16 array, dimension (LDB,N) */
/* The triangular factor from the Cholesky factorization of B, */
/* as returned by ZPOTRF. */
/* LDB (input) INTEGER */
/* The leading dimension of the array B. LDB >= max(1,N). */
/* INFO (output) INTEGER */
/* = 0: successful exit. */
/* < 0: if INFO = -i, the i-th argument had an illegal value. */
/* ===================================================================== */
/* Test the input parameters. */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
b_dim1 = *ldb;
b_offset = 1 + b_dim1;
b -= b_offset;
/* Function Body */
*info = 0;
upper = lsame_(uplo, "U");
if (*itype < 1 || *itype > 3) {
*info = -1;
} else if (! upper && ! lsame_(uplo, "L")) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*lda < max(1,*n)) {
*info = -5;
} else if (*ldb < max(1,*n)) {
*info = -7;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHEGS2", &i__1);
return 0;
}
if (*itype == 1) {
if (upper) {
/* Compute inv(U')*A*inv(U) */
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
/* Update the upper triangle of A(k:n,k:n) */
i__2 = k + k * a_dim1;
akk = a[i__2].r;
i__2 = k + k * b_dim1;
bkk = b[i__2].r;
/* Computing 2nd power */
d__1 = bkk;
akk /= d__1 * d__1;
i__2 = k + k * a_dim1;
a[i__2].r = akk, a[i__2].i = 0.;
if (k < *n) {
i__2 = *n - k;
d__1 = 1. / bkk;
zdscal_(&i__2, &d__1, &a[k + (k + 1) * a_dim1], lda);
d__1 = akk * -.5;
ct.r = d__1, ct.i = 0.;
i__2 = *n - k;
zlacgv_(&i__2, &a[k + (k + 1) * a_dim1], lda);
i__2 = *n - k;
zlacgv_(&i__2, &b[k + (k + 1) * b_dim1], ldb);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &b[k + (k + 1) * b_dim1], ldb, &a[k + (
k + 1) * a_dim1], lda);
i__2 = *n - k;
z__1.r = -1., z__1.i = -0.;
zher2_(uplo, &i__2, &z__1, &a[k + (k + 1) * a_dim1], lda,
&b[k + (k + 1) * b_dim1], ldb, &a[k + 1 + (k + 1)
* a_dim1], lda);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &b[k + (k + 1) * b_dim1], ldb, &a[k + (
k + 1) * a_dim1], lda);
i__2 = *n - k;
zlacgv_(&i__2, &b[k + (k + 1) * b_dim1], ldb);
i__2 = *n - k;
ztrsv_(uplo, "Conjugate transpose", "Non-unit", &i__2, &b[
k + 1 + (k + 1) * b_dim1], ldb, &a[k + (k + 1) *
a_dim1], lda);
i__2 = *n - k;
zlacgv_(&i__2, &a[k + (k + 1) * a_dim1], lda);
}
}
} else {
/* Compute inv(L)*A*inv(L') */
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
/* Update the lower triangle of A(k:n,k:n) */
i__2 = k + k * a_dim1;
akk = a[i__2].r;
i__2 = k + k * b_dim1;
bkk = b[i__2].r;
/* Computing 2nd power */
d__1 = bkk;
akk /= d__1 * d__1;
i__2 = k + k * a_dim1;
a[i__2].r = akk, a[i__2].i = 0.;
if (k < *n) {
i__2 = *n - k;
d__1 = 1. / bkk;
zdscal_(&i__2, &d__1, &a[k + 1 + k * a_dim1], &c__1);
d__1 = akk * -.5;
ct.r = d__1, ct.i = 0.;
i__2 = *n - k;
zaxpy_(&i__2, &ct, &b[k + 1 + k * b_dim1], &c__1, &a[k +
1 + k * a_dim1], &c__1);
i__2 = *n - k;
z__1.r = -1., z__1.i = -0.;
zher2_(uplo, &i__2, &z__1, &a[k + 1 + k * a_dim1], &c__1,
&b[k + 1 + k * b_dim1], &c__1, &a[k + 1 + (k + 1)
* a_dim1], lda);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &b[k + 1 + k * b_dim1], &c__1, &a[k +
1 + k * a_dim1], &c__1);
i__2 = *n - k;
ztrsv_(uplo, "No transpose", "Non-unit", &i__2, &b[k + 1
+ (k + 1) * b_dim1], ldb, &a[k + 1 + k * a_dim1],
&c__1);
}
}
}
} else {
if (upper) {
/* Compute U*A*U' */
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
/* Update the upper triangle of A(1:k,1:k) */
i__2 = k + k * a_dim1;
akk = a[i__2].r;
i__2 = k + k * b_dim1;
bkk = b[i__2].r;
i__2 = k - 1;
ztrmv_(uplo, "No transpose", "Non-unit", &i__2, &b[b_offset],
ldb, &a[k * a_dim1 + 1], &c__1);
d__1 = akk * .5;
ct.r = d__1, ct.i = 0.;
i__2 = k - 1;
zaxpy_(&i__2, &ct, &b[k * b_dim1 + 1], &c__1, &a[k * a_dim1 +
1], &c__1);
i__2 = k - 1;
zher2_(uplo, &i__2, &c_b1, &a[k * a_dim1 + 1], &c__1, &b[k *
b_dim1 + 1], &c__1, &a[a_offset], lda);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &b[k * b_dim1 + 1], &c__1, &a[k * a_dim1 +
1], &c__1);
i__2 = k - 1;
zdscal_(&i__2, &bkk, &a[k * a_dim1 + 1], &c__1);
i__2 = k + k * a_dim1;
/* Computing 2nd power */
d__2 = bkk;
d__1 = akk * (d__2 * d__2);
a[i__2].r = d__1, a[i__2].i = 0.;
}
} else {
/* Compute L'*A*L */
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
/* Update the lower triangle of A(1:k,1:k) */
i__2 = k + k * a_dim1;
akk = a[i__2].r;
i__2 = k + k * b_dim1;
bkk = b[i__2].r;
i__2 = k - 1;
zlacgv_(&i__2, &a[k + a_dim1], lda);
i__2 = k - 1;
ztrmv_(uplo, "Conjugate transpose", "Non-unit", &i__2, &b[
b_offset], ldb, &a[k + a_dim1], lda);
d__1 = akk * .5;
ct.r = d__1, ct.i = 0.;
i__2 = k - 1;
zlacgv_(&i__2, &b[k + b_dim1], ldb);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &b[k + b_dim1], ldb, &a[k + a_dim1], lda);
i__2 = k - 1;
zher2_(uplo, &i__2, &c_b1, &a[k + a_dim1], lda, &b[k + b_dim1]
, ldb, &a[a_offset], lda);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &b[k + b_dim1], ldb, &a[k + a_dim1], lda);
i__2 = k - 1;
zlacgv_(&i__2, &b[k + b_dim1], ldb);
i__2 = k - 1;
zdscal_(&i__2, &bkk, &a[k + a_dim1], lda);
i__2 = k - 1;
zlacgv_(&i__2, &a[k + a_dim1], lda);
i__2 = k + k * a_dim1;
/* Computing 2nd power */
d__2 = bkk;
d__1 = akk * (d__2 * d__2);
a[i__2].r = d__1, a[i__2].i = 0.;
}
}
}
return 0;
/* End of ZHEGS2 */
} /* zhegs2_ */
/* Subroutine */ int zhegs2_(integer *itype, char *uplo, integer *n,
doublecomplex *a, integer *lda, doublecomplex *b, integer *ldb,
integer *info)
{
/* -- LAPACK routine (version 2.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
September 30, 1994
Purpose
=======
ZHEGS2 reduces a complex Hermitian-definite generalized
eigenproblem to standard form.
If ITYPE = 1, the problem is A*x = lambda*B*x,
and A is overwritten by inv(U')*A*inv(U) or inv(L)*A*inv(L')
If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or
B*A*x = lambda*x, and A is overwritten by U*A*U` or L'*A*L.
B must have been previously factorized as U'*U or L*L' by ZPOTRF.
Arguments
=========
ITYPE (input) INTEGER
= 1: compute inv(U')*A*inv(U) or inv(L)*A*inv(L');
= 2 or 3: compute U*A*U' or L'*A*L.
UPLO (input) CHARACTER
Specifies whether the upper or lower triangular part of the
Hermitian matrix A is stored, and how B has been factorized.
= 'U': Upper triangular
= 'L': Lower triangular
N (input) INTEGER
The order of the matrices A and B. N >= 0.
A (input/output) COMPLEX*16 array, dimension (LDA,N)
On entry, the Hermitian matrix A. If UPLO = 'U', the leading
n by n upper triangular part of A contains the upper
triangular part of the matrix A, and the strictly lower
triangular part of A is not referenced. If UPLO = 'L', the
leading n by n lower triangular part of A contains the lower
triangular part of the matrix A, and the strictly upper
triangular part of A is not referenced.
On exit, if INFO = 0, the transformed matrix, stored in the
same format as A.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
B (input) COMPLEX*16 array, dimension (LDB,N)
The triangular factor from the Cholesky factorization of B,
as returned by ZPOTRF.
LDB (input) INTEGER
The leading dimension of the array B. LDB >= max(1,N).
INFO (output) INTEGER
= 0: successful exit.
< 0: if INFO = -i, the i-th argument had an illegal value.
=====================================================================
Test the input parameters.
Parameter adjustments
Function Body */
/* Table of constant values */
static doublecomplex c_b1 = {1.,0.};
static integer c__1 = 1;
/* System generated locals */
integer a_dim1, a_offset, b_dim1, b_offset, i__1, i__2;
doublereal d__1, d__2;
doublecomplex z__1;
/* Local variables */
extern /* Subroutine */ int zher2_(char *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
static integer k;
extern logical lsame_(char *, char *);
static logical upper;
extern /* Subroutine */ int zaxpy_(integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *), ztrmv_(
char *, char *, char *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *), ztrsv_(char *
, char *, char *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
static doublecomplex ct;
extern /* Subroutine */ int xerbla_(char *, integer *), zdscal_(
integer *, doublereal *, doublecomplex *, integer *), zlacgv_(
integer *, doublecomplex *, integer *);
static doublereal akk, bkk;
#define A(I,J) a[(I)-1 + ((J)-1)* ( *lda)]
#define B(I,J) b[(I)-1 + ((J)-1)* ( *ldb)]
*info = 0;
upper = lsame_(uplo, "U");
if (*itype < 1 || *itype > 3) {
*info = -1;
} else if (! upper && ! lsame_(uplo, "L")) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*lda < max(1,*n)) {
*info = -5;
} else if (*ldb < max(1,*n)) {
*info = -7;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHEGS2", &i__1);
return 0;
}
if (*itype == 1) {
if (upper) {
/* Compute inv(U')*A*inv(U) */
i__1 = *n;
for (k = 1; k <= *n; ++k) {
/* Update the upper triangle of A(k:n,k:n) */
i__2 = k + k * a_dim1;
akk = A(k,k).r;
i__2 = k + k * b_dim1;
bkk = B(k,k).r;
/* Computing 2nd power */
d__1 = bkk;
akk /= d__1 * d__1;
i__2 = k + k * a_dim1;
A(k,k).r = akk, A(k,k).i = 0.;
if (k < *n) {
i__2 = *n - k;
d__1 = 1. / bkk;
zdscal_(&i__2, &d__1, &A(k,k+1), lda);
d__1 = akk * -.5;
ct.r = d__1, ct.i = 0.;
i__2 = *n - k;
zlacgv_(&i__2, &A(k,k+1), lda);
i__2 = *n - k;
zlacgv_(&i__2, &B(k,k+1), ldb);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &B(k,k+1), ldb, &A(k,k+1), lda);
i__2 = *n - k;
z__1.r = -1., z__1.i = 0.;
zher2_(uplo, &i__2, &z__1, &A(k,k+1), lda,
&B(k,k+1), ldb, &A(k+1,k+1), lda);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &B(k,k+1), ldb, &A(k,k+1), lda);
i__2 = *n - k;
zlacgv_(&i__2, &B(k,k+1), ldb);
i__2 = *n - k;
ztrsv_(uplo, "Conjugate transpose", "Non-unit", &i__2, &B(k+1,k+1), ldb, &A(k,k+1), lda);
i__2 = *n - k;
zlacgv_(&i__2, &A(k,k+1), lda);
}
/* L10: */
}
} else {
/* Compute inv(L)*A*inv(L') */
i__1 = *n;
for (k = 1; k <= *n; ++k) {
/* Update the lower triangle of A(k:n,k:n) */
i__2 = k + k * a_dim1;
akk = A(k,k).r;
i__2 = k + k * b_dim1;
bkk = B(k,k).r;
/* Computing 2nd power */
d__1 = bkk;
akk /= d__1 * d__1;
i__2 = k + k * a_dim1;
A(k,k).r = akk, A(k,k).i = 0.;
if (k < *n) {
i__2 = *n - k;
d__1 = 1. / bkk;
zdscal_(&i__2, &d__1, &A(k+1,k), &c__1);
d__1 = akk * -.5;
ct.r = d__1, ct.i = 0.;
i__2 = *n - k;
zaxpy_(&i__2, &ct, &B(k+1,k), &c__1, &A(k+1,k), &c__1);
i__2 = *n - k;
z__1.r = -1., z__1.i = 0.;
zher2_(uplo, &i__2, &z__1, &A(k+1,k), &c__1,
&B(k+1,k), &c__1, &A(k+1,k+1), lda);
i__2 = *n - k;
zaxpy_(&i__2, &ct, &B(k+1,k), &c__1, &A(k+1,k), &c__1);
i__2 = *n - k;
ztrsv_(uplo, "No transpose", "Non-unit", &i__2, &B(k+1,k+1), ldb, &A(k+1,k),
&c__1);
}
/* L20: */
}
}
} else {
if (upper) {
/* Compute U*A*U' */
i__1 = *n;
for (k = 1; k <= *n; ++k) {
/* Update the upper triangle of A(1:k,1:k) */
i__2 = k + k * a_dim1;
akk = A(k,k).r;
i__2 = k + k * b_dim1;
bkk = B(k,k).r;
i__2 = k - 1;
ztrmv_(uplo, "No transpose", "Non-unit", &i__2, &B(1,1),
ldb, &A(1,k), &c__1);
d__1 = akk * .5;
ct.r = d__1, ct.i = 0.;
i__2 = k - 1;
zaxpy_(&i__2, &ct, &B(1,k), &c__1, &A(1,k), &c__1);
i__2 = k - 1;
zher2_(uplo, &i__2, &c_b1, &A(1,k), &c__1, &B(1,k), &c__1, &A(1,1), lda);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &B(1,k), &c__1, &A(1,k), &c__1);
i__2 = k - 1;
zdscal_(&i__2, &bkk, &A(1,k), &c__1);
i__2 = k + k * a_dim1;
/* Computing 2nd power */
d__2 = bkk;
d__1 = akk * (d__2 * d__2);
A(k,k).r = d__1, A(k,k).i = 0.;
/* L30: */
}
} else {
/* Compute L'*A*L */
i__1 = *n;
for (k = 1; k <= *n; ++k) {
/* Update the lower triangle of A(1:k,1:k) */
i__2 = k + k * a_dim1;
akk = A(k,k).r;
i__2 = k + k * b_dim1;
bkk = B(k,k).r;
i__2 = k - 1;
zlacgv_(&i__2, &A(k,1), lda);
i__2 = k - 1;
ztrmv_(uplo, "Conjugate transpose", "Non-unit", &i__2, &B(1,1), ldb, &A(k,1), lda);
d__1 = akk * .5;
ct.r = d__1, ct.i = 0.;
i__2 = k - 1;
zlacgv_(&i__2, &B(k,1), ldb);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &B(k,1), ldb, &A(k,1), lda);
i__2 = k - 1;
zher2_(uplo, &i__2, &c_b1, &A(k,1), lda, &B(k,1)
, ldb, &A(1,1), lda);
i__2 = k - 1;
zaxpy_(&i__2, &ct, &B(k,1), ldb, &A(k,1), lda);
i__2 = k - 1;
zlacgv_(&i__2, &B(k,1), ldb);
i__2 = k - 1;
zdscal_(&i__2, &bkk, &A(k,1), lda);
i__2 = k - 1;
zlacgv_(&i__2, &A(k,1), lda);
i__2 = k + k * a_dim1;
/* Computing 2nd power */
d__2 = bkk;
d__1 = akk * (d__2 * d__2);
A(k,k).r = d__1, A(k,k).i = 0.;
/* L40: */
}
}
}
return 0;
/* End of ZHEGS2 */
} /* zhegs2_ */
/* Subroutine */ int zhet21_(integer *itype, char *uplo, integer *n, integer *
kband, doublecomplex *a, integer *lda, doublereal *d__, doublereal *e,
doublecomplex *u, integer *ldu, doublecomplex *v, integer *ldv,
doublecomplex *tau, doublecomplex *work, doublereal *rwork,
doublereal *result)
{
/* System generated locals */
integer a_dim1, a_offset, u_dim1, u_offset, v_dim1, v_offset, i__1, i__2,
i__3, i__4, i__5, i__6;
doublereal d__1, d__2;
doublecomplex z__1, z__2, z__3;
/* Local variables */
integer j, jr;
doublereal ulp;
integer jcol;
doublereal unfl;
extern /* Subroutine */ int zher_(char *, integer *, doublereal *,
doublecomplex *, integer *, doublecomplex *, integer *);
integer jrow;
extern /* Subroutine */ int zher2_(char *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
extern logical lsame_(char *, char *);
integer iinfo;
doublereal anorm;
extern /* Subroutine */ int zgemm_(char *, char *, integer *, integer *,
integer *, doublecomplex *, doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *);
char cuplo[1];
doublecomplex vsave;
logical lower;
doublereal wnorm;
extern /* Subroutine */ int zunm2l_(char *, char *, integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *);
extern doublereal dlamch_(char *);
extern /* Subroutine */ int zunm2r_(char *, char *, integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *);
extern doublereal zlange_(char *, integer *, integer *, doublecomplex *,
integer *, doublereal *), zlanhe_(char *, char *, integer
*, doublecomplex *, integer *, doublereal *);
extern /* Subroutine */ int zlacpy_(char *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *),
zlaset_(char *, integer *, integer *, doublecomplex *,
doublecomplex *, doublecomplex *, integer *), zlarfy_(
char *, integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *);
/* -- LAPACK test routine (version 3.1) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZHET21 generally checks a decomposition of the form */
/* A = U S U* */
/* where * means conjugate transpose, A is hermitian, U is unitary, and */
/* S is diagonal (if KBAND=0) or (real) symmetric tridiagonal (if */
/* KBAND=1). */
/* If ITYPE=1, then U is represented as a dense matrix; otherwise U is */
/* expressed as a product of Householder transformations, whose vectors */
/* are stored in the array "V" and whose scaling constants are in "TAU". */
/* We shall use the letter "V" to refer to the product of Householder */
/* transformations (which should be equal to U). */
/* Specifically, if ITYPE=1, then: */
/* RESULT(1) = | A - U S U* | / ( |A| n ulp ) *and* */
/* RESULT(2) = | I - UU* | / ( n ulp ) */
/* If ITYPE=2, then: */
/* RESULT(1) = | A - V S V* | / ( |A| n ulp ) */
/* If ITYPE=3, then: */
/* RESULT(1) = | I - UV* | / ( n ulp ) */
/* For ITYPE > 1, the transformation U is expressed as a product */
/* V = H(1)...H(n-2), where H(j) = I - tau(j) v(j) v(j)* and each */
/* vector v(j) has its first j elements 0 and the remaining n-j elements */
/* stored in V(j+1:n,j). */
/* Arguments */
/* ========= */
/* ITYPE (input) INTEGER */
/* Specifies the type of tests to be performed. */
/* 1: U expressed as a dense unitary matrix: */
/* RESULT(1) = | A - U S U* | / ( |A| n ulp ) *and* */
/* RESULT(2) = | I - UU* | / ( n ulp ) */
/* 2: U expressed as a product V of Housholder transformations: */
/* RESULT(1) = | A - V S V* | / ( |A| n ulp ) */
/* 3: U expressed both as a dense unitary matrix and */
/* as a product of Housholder transformations: */
/* RESULT(1) = | I - UV* | / ( n ulp ) */
/* UPLO (input) CHARACTER */
/* If UPLO='U', the upper triangle of A and V will be used and */
/* the (strictly) lower triangle will not be referenced. */
/* If UPLO='L', the lower triangle of A and V will be used and */
/* the (strictly) upper triangle will not be referenced. */
/* N (input) INTEGER */
/* The size of the matrix. If it is zero, ZHET21 does nothing. */
/* It must be at least zero. */
/* KBAND (input) INTEGER */
/* The bandwidth of the matrix. It may only be zero or one. */
/* If zero, then S is diagonal, and E is not referenced. If */
/* one, then S is symmetric tri-diagonal. */
/* A (input) COMPLEX*16 array, dimension (LDA, N) */
/* The original (unfactored) matrix. It is assumed to be */
/* hermitian, and only the upper (UPLO='U') or only the lower */
/* (UPLO='L') will be referenced. */
/* LDA (input) INTEGER */
/* The leading dimension of A. It must be at least 1 */
/* and at least N. */
/* D (input) DOUBLE PRECISION array, dimension (N) */
/* The diagonal of the (symmetric tri-) diagonal matrix. */
/* E (input) DOUBLE PRECISION array, dimension (N-1) */
/* The off-diagonal of the (symmetric tri-) diagonal matrix. */
/* E(1) is the (1,2) and (2,1) element, E(2) is the (2,3) and */
/* (3,2) element, etc. */
/* Not referenced if KBAND=0. */
/* U (input) COMPLEX*16 array, dimension (LDU, N) */
/* If ITYPE=1 or 3, this contains the unitary matrix in */
/* the decomposition, expressed as a dense matrix. If ITYPE=2, */
/* then it is not referenced. */
/* LDU (input) INTEGER */
/* The leading dimension of U. LDU must be at least N and */
/* at least 1. */
/* V (input) COMPLEX*16 array, dimension (LDV, N) */
/* If ITYPE=2 or 3, the columns of this array contain the */
/* Householder vectors used to describe the unitary matrix */
/* in the decomposition. If UPLO='L', then the vectors are in */
/* the lower triangle, if UPLO='U', then in the upper */
/* triangle. */
/* *NOTE* If ITYPE=2 or 3, V is modified and restored. The */
/* subdiagonal (if UPLO='L') or the superdiagonal (if UPLO='U') */
/* is set to one, and later reset to its original value, during */
/* the course of the calculation. */
/* If ITYPE=1, then it is neither referenced nor modified. */
/* LDV (input) INTEGER */
/* The leading dimension of V. LDV must be at least N and */
/* at least 1. */
/* TAU (input) COMPLEX*16 array, dimension (N) */
/* If ITYPE >= 2, then TAU(j) is the scalar factor of */
/* v(j) v(j)* in the Householder transformation H(j) of */
/* the product U = H(1)...H(n-2) */
/* If ITYPE < 2, then TAU is not referenced. */
/* WORK (workspace) COMPLEX*16 array, dimension (2*N**2) */
/* RWORK (workspace) DOUBLE PRECISION array, dimension (N) */
/* RESULT (output) DOUBLE PRECISION array, dimension (2) */
/* The values computed by the two tests described above. The */
/* values are currently limited to 1/ulp, to avoid overflow. */
/* RESULT(1) is always modified. RESULT(2) is modified only */
/* if ITYPE=1. */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
--d__;
--e;
u_dim1 = *ldu;
u_offset = 1 + u_dim1;
u -= u_offset;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--tau;
--work;
--rwork;
--result;
/* Function Body */
result[1] = 0.;
if (*itype == 1) {
result[2] = 0.;
}
if (*n <= 0) {
return 0;
}
if (lsame_(uplo, "U")) {
lower = FALSE_;
*(unsigned char *)cuplo = 'U';
} else {
lower = TRUE_;
*(unsigned char *)cuplo = 'L';
}
unfl = dlamch_("Safe minimum");
ulp = dlamch_("Epsilon") * dlamch_("Base");
/* Some Error Checks */
if (*itype < 1 || *itype > 3) {
result[1] = 10. / ulp;
return 0;
}
/* Do Test 1 */
/* Norm of A: */
if (*itype == 3) {
anorm = 1.;
} else {
/* Computing MAX */
d__1 = zlanhe_("1", cuplo, n, &a[a_offset], lda, &rwork[1]);
anorm = max(d__1,unfl);
}
/* Compute error matrix: */
if (*itype == 1) {
/* ITYPE=1: error = A - U S U* */
zlaset_("Full", n, n, &c_b1, &c_b1, &work[1], n);
zlacpy_(cuplo, n, n, &a[a_offset], lda, &work[1], n);
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
d__1 = -d__[j];
zher_(cuplo, n, &d__1, &u[j * u_dim1 + 1], &c__1, &work[1], n);
/* L10: */
}
if (*n > 1 && *kband == 1) {
i__1 = *n - 1;
for (j = 1; j <= i__1; ++j) {
i__2 = j;
z__2.r = e[i__2], z__2.i = 0.;
z__1.r = -z__2.r, z__1.i = -z__2.i;
zher2_(cuplo, n, &z__1, &u[j * u_dim1 + 1], &c__1, &u[(j - 1)
* u_dim1 + 1], &c__1, &work[1], n);
/* L20: */
}
}
wnorm = zlanhe_("1", cuplo, n, &work[1], n, &rwork[1]);
} else if (*itype == 2) {
/* ITYPE=2: error = V S V* - A */
zlaset_("Full", n, n, &c_b1, &c_b1, &work[1], n);
if (lower) {
/* Computing 2nd power */
i__2 = *n;
i__1 = i__2 * i__2;
i__3 = *n;
work[i__1].r = d__[i__3], work[i__1].i = 0.;
for (j = *n - 1; j >= 1; --j) {
if (*kband == 1) {
i__1 = (*n + 1) * (j - 1) + 2;
i__2 = j;
z__2.r = 1. - tau[i__2].r, z__2.i = 0. - tau[i__2].i;
i__3 = j;
z__1.r = e[i__3] * z__2.r, z__1.i = e[i__3] * z__2.i;
work[i__1].r = z__1.r, work[i__1].i = z__1.i;
i__1 = *n;
for (jr = j + 2; jr <= i__1; ++jr) {
i__2 = (j - 1) * *n + jr;
i__3 = j;
z__3.r = -tau[i__3].r, z__3.i = -tau[i__3].i;
i__4 = j;
z__2.r = e[i__4] * z__3.r, z__2.i = e[i__4] * z__3.i;
i__5 = jr + j * 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;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L30: */
}
}
i__1 = j + 1 + j * v_dim1;
vsave.r = v[i__1].r, vsave.i = v[i__1].i;
i__1 = j + 1 + j * v_dim1;
v[i__1].r = 1., v[i__1].i = 0.;
i__1 = *n - j;
/* Computing 2nd power */
i__2 = *n;
zlarfy_("L", &i__1, &v[j + 1 + j * v_dim1], &c__1, &tau[j], &
work[(*n + 1) * j + 1], n, &work[i__2 * i__2 + 1]);
i__1 = j + 1 + j * v_dim1;
v[i__1].r = vsave.r, v[i__1].i = vsave.i;
i__1 = (*n + 1) * (j - 1) + 1;
i__2 = j;
work[i__1].r = d__[i__2], work[i__1].i = 0.;
/* L40: */
}
} else {
work[1].r = d__[1], work[1].i = 0.;
i__1 = *n - 1;
for (j = 1; j <= i__1; ++j) {
if (*kband == 1) {
i__2 = (*n + 1) * j;
i__3 = j;
z__2.r = 1. - tau[i__3].r, z__2.i = 0. - tau[i__3].i;
i__4 = j;
z__1.r = e[i__4] * z__2.r, z__1.i = e[i__4] * z__2.i;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
i__2 = j - 1;
for (jr = 1; jr <= i__2; ++jr) {
i__3 = j * *n + jr;
i__4 = j;
z__3.r = -tau[i__4].r, z__3.i = -tau[i__4].i;
i__5 = j;
z__2.r = e[i__5] * z__3.r, z__2.i = e[i__5] * z__3.i;
i__6 = jr + (j + 1) * v_dim1;
z__1.r = z__2.r * v[i__6].r - z__2.i * v[i__6].i,
z__1.i = z__2.r * v[i__6].i + z__2.i * v[i__6]
.r;
work[i__3].r = z__1.r, work[i__3].i = z__1.i;
/* L50: */
}
}
i__2 = j + (j + 1) * v_dim1;
vsave.r = v[i__2].r, vsave.i = v[i__2].i;
i__2 = j + (j + 1) * v_dim1;
v[i__2].r = 1., v[i__2].i = 0.;
/* Computing 2nd power */
i__2 = *n;
zlarfy_("U", &j, &v[(j + 1) * v_dim1 + 1], &c__1, &tau[j], &
work[1], n, &work[i__2 * i__2 + 1]);
i__2 = j + (j + 1) * v_dim1;
v[i__2].r = vsave.r, v[i__2].i = vsave.i;
i__2 = (*n + 1) * j + 1;
i__3 = j + 1;
work[i__2].r = d__[i__3], work[i__2].i = 0.;
/* L60: */
}
}
i__1 = *n;
for (jcol = 1; jcol <= i__1; ++jcol) {
if (lower) {
i__2 = *n;
for (jrow = jcol; jrow <= i__2; ++jrow) {
i__3 = jrow + *n * (jcol - 1);
i__4 = jrow + *n * (jcol - 1);
i__5 = jrow + jcol * a_dim1;
z__1.r = work[i__4].r - a[i__5].r, z__1.i = work[i__4].i
- a[i__5].i;
work[i__3].r = z__1.r, work[i__3].i = z__1.i;
/* L70: */
}
} else {
i__2 = jcol;
for (jrow = 1; jrow <= i__2; ++jrow) {
i__3 = jrow + *n * (jcol - 1);
i__4 = jrow + *n * (jcol - 1);
i__5 = jrow + jcol * a_dim1;
z__1.r = work[i__4].r - a[i__5].r, z__1.i = work[i__4].i
- a[i__5].i;
work[i__3].r = z__1.r, work[i__3].i = z__1.i;
/* L80: */
}
}
/* L90: */
}
wnorm = zlanhe_("1", cuplo, n, &work[1], n, &rwork[1]);
} else if (*itype == 3) {
/* ITYPE=3: error = U V* - I */
if (*n < 2) {
return 0;
}
zlacpy_(" ", n, n, &u[u_offset], ldu, &work[1], n);
if (lower) {
i__1 = *n - 1;
i__2 = *n - 1;
/* Computing 2nd power */
i__3 = *n;
zunm2r_("R", "C", n, &i__1, &i__2, &v[v_dim1 + 2], ldv, &tau[1], &
work[*n + 1], n, &work[i__3 * i__3 + 1], &iinfo);
} else {
i__1 = *n - 1;
i__2 = *n - 1;
/* Computing 2nd power */
i__3 = *n;
zunm2l_("R", "C", n, &i__1, &i__2, &v[(v_dim1 << 1) + 1], ldv, &
tau[1], &work[1], n, &work[i__3 * i__3 + 1], &iinfo);
}
if (iinfo != 0) {
result[1] = 10. / ulp;
return 0;
}
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = (*n + 1) * (j - 1) + 1;
i__3 = (*n + 1) * (j - 1) + 1;
z__1.r = work[i__3].r - 1., z__1.i = work[i__3].i - 0.;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L100: */
}
wnorm = zlange_("1", n, n, &work[1], n, &rwork[1]);
}
if (anorm > wnorm) {
result[1] = wnorm / anorm / (*n * ulp);
} else {
if (anorm < 1.) {
/* Computing MIN */
d__1 = wnorm, d__2 = *n * anorm;
result[1] = min(d__1,d__2) / anorm / (*n * ulp);
} else {
/* Computing MIN */
d__1 = wnorm / anorm, d__2 = (doublereal) (*n);
result[1] = min(d__1,d__2) / (*n * ulp);
}
}
/* Do Test 2 */
/* Compute UU* - I */
if (*itype == 1) {
zgemm_("N", "C", n, n, n, &c_b2, &u[u_offset], ldu, &u[u_offset], ldu,
&c_b1, &work[1], n);
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
i__2 = (*n + 1) * (j - 1) + 1;
i__3 = (*n + 1) * (j - 1) + 1;
z__1.r = work[i__3].r - 1., z__1.i = work[i__3].i - 0.;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L110: */
}
/* Computing MIN */
d__1 = zlange_("1", n, n, &work[1], n, &rwork[1]), d__2 = (
doublereal) (*n);
result[2] = min(d__1,d__2) / (*n * ulp);
}
return 0;
/* End of ZHET21 */
} /* zhet21_ */
int zhetd2_(char *uplo, int *n, doublecomplex *a,
int *lda, double *d__, double *e, doublecomplex *tau,
int *info)
{
/* System generated locals */
int a_dim1, a_offset, i__1, i__2, i__3;
double d__1;
doublecomplex z__1, z__2, z__3, z__4;
/* Local variables */
int i__;
doublecomplex taui;
extern int zher2_(char *, int *, doublecomplex *,
doublecomplex *, int *, doublecomplex *, int *,
doublecomplex *, int *);
doublecomplex alpha;
extern int lsame_(char *, char *);
extern /* Double Complex */ VOID zdotc_(doublecomplex *, int *,
doublecomplex *, int *, doublecomplex *, int *);
extern int zhemv_(char *, int *, doublecomplex *,
doublecomplex *, int *, doublecomplex *, int *,
doublecomplex *, doublecomplex *, int *);
int upper;
extern int zaxpy_(int *, doublecomplex *,
doublecomplex *, int *, doublecomplex *, int *), xerbla_(
char *, int *), zlarfg_(int *, doublecomplex *,
doublecomplex *, int *, doublecomplex *);
/* -- LAPACK routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZHETD2 reduces a complex Hermitian matrix A to float symmetric */
/* tridiagonal form T by a unitary similarity transformation: */
/* Q' * A * Q = T. */
/* Arguments */
/* ========= */
/* UPLO (input) CHARACTER*1 */
/* Specifies whether the upper or lower triangular part of the */
/* Hermitian matrix A is stored: */
/* = 'U': Upper triangular */
/* = 'L': Lower triangular */
/* N (input) INTEGER */
/* The order of the matrix A. N >= 0. */
/* A (input/output) COMPLEX*16 array, dimension (LDA,N) */
/* On entry, the Hermitian matrix A. If UPLO = 'U', the leading */
/* n-by-n upper triangular part of A contains the upper */
/* triangular part of the matrix A, and the strictly lower */
/* triangular part of A is not referenced. If UPLO = 'L', the */
/* leading n-by-n lower triangular part of A contains the lower */
/* triangular part of the matrix A, and the strictly upper */
/* triangular part of A is not referenced. */
/* On exit, if UPLO = 'U', the diagonal and first superdiagonal */
/* of A are overwritten by the corresponding elements of the */
/* tridiagonal matrix T, and the elements above the first */
/* superdiagonal, with the array TAU, represent the unitary */
/* matrix Q as a product of elementary reflectors; if UPLO */
/* = 'L', the diagonal and first subdiagonal of A are over- */
/* written by the corresponding elements of the tridiagonal */
/* matrix T, and the elements below the first subdiagonal, with */
/* the array TAU, represent the unitary matrix Q as a product */
/* of elementary reflectors. See Further Details. */
/* LDA (input) INTEGER */
/* The leading dimension of the array A. LDA >= MAX(1,N). */
/* D (output) DOUBLE PRECISION array, dimension (N) */
/* The diagonal elements of the tridiagonal matrix T: */
/* D(i) = A(i,i). */
/* E (output) DOUBLE PRECISION array, dimension (N-1) */
/* The off-diagonal elements of the tridiagonal matrix T: */
/* E(i) = A(i,i+1) if UPLO = 'U', E(i) = A(i+1,i) if UPLO = 'L'. */
/* TAU (output) COMPLEX*16 array, dimension (N-1) */
/* The scalar factors of the elementary reflectors (see Further */
/* Details). */
/* INFO (output) INTEGER */
/* = 0: successful exit */
/* < 0: if INFO = -i, the i-th argument had an illegal value. */
/* Further Details */
/* =============== */
/* If UPLO = 'U', the matrix Q is represented as a product of elementary */
/* reflectors */
/* Q = H(n-1) . . . H(2) H(1). */
/* Each H(i) has the form */
/* H(i) = I - tau * v * v' */
/* where tau is a complex scalar, and v is a complex vector with */
/* v(i+1:n) = 0 and v(i) = 1; v(1:i-1) is stored on exit in */
/* A(1:i-1,i+1), and tau in TAU(i). */
/* If UPLO = 'L', the matrix Q is represented as a product of elementary */
/* reflectors */
/* Q = H(1) H(2) . . . H(n-1). */
/* Each H(i) has the form */
/* H(i) = I - tau * v * v' */
/* where tau is a complex scalar, and v is a complex vector with */
/* v(1:i) = 0 and v(i+1) = 1; v(i+2:n) is stored on exit in A(i+2:n,i), */
/* and tau in TAU(i). */
/* The contents of A on exit are illustrated by the following examples */
/* with n = 5: */
/* if UPLO = 'U': if UPLO = 'L': */
/* ( d e v2 v3 v4 ) ( d ) */
/* ( d e v3 v4 ) ( e d ) */
/* ( d e v4 ) ( v1 e d ) */
/* ( d e ) ( v1 v2 e d ) */
/* ( d ) ( v1 v2 v3 e d ) */
/* where d and e denote diagonal and off-diagonal elements of T, and vi */
/* denotes an element of the vector defining H(i). */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Test the input parameters */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
--d__;
--e;
--tau;
/* Function Body */
*info = 0;
upper = lsame_(uplo, "U");
if (! upper && ! lsame_(uplo, "L")) {
*info = -1;
} else if (*n < 0) {
*info = -2;
} else if (*lda < MAX(1,*n)) {
*info = -4;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHETD2", &i__1);
return 0;
}
/* Quick return if possible */
if (*n <= 0) {
return 0;
}
if (upper) {
/* Reduce the upper triangle of A */
i__1 = *n + *n * a_dim1;
i__2 = *n + *n * a_dim1;
d__1 = a[i__2].r;
a[i__1].r = d__1, a[i__1].i = 0.;
for (i__ = *n - 1; i__ >= 1; --i__) {
/* Generate elementary reflector H(i) = I - tau * v * v' */
/* to annihilate A(1:i-1,i+1) */
i__1 = i__ + (i__ + 1) * a_dim1;
alpha.r = a[i__1].r, alpha.i = a[i__1].i;
zlarfg_(&i__, &alpha, &a[(i__ + 1) * a_dim1 + 1], &c__1, &taui);
i__1 = i__;
e[i__1] = alpha.r;
if (taui.r != 0. || taui.i != 0.) {
/* Apply H(i) from both sides to A(1:i,1:i) */
i__1 = i__ + (i__ + 1) * a_dim1;
a[i__1].r = 1., a[i__1].i = 0.;
/* Compute x := tau * A * v storing x in TAU(1:i) */
zhemv_(uplo, &i__, &taui, &a[a_offset], lda, &a[(i__ + 1) *
a_dim1 + 1], &c__1, &c_b2, &tau[1], &c__1);
/* Compute w := x - 1/2 * tau * (x'*v) * v */
z__3.r = -.5, z__3.i = -0.;
z__2.r = z__3.r * taui.r - z__3.i * taui.i, z__2.i = z__3.r *
taui.i + z__3.i * taui.r;
zdotc_(&z__4, &i__, &tau[1], &c__1, &a[(i__ + 1) * a_dim1 + 1]
, &c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r *
z__4.i + z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
zaxpy_(&i__, &alpha, &a[(i__ + 1) * a_dim1 + 1], &c__1, &tau[
1], &c__1);
/* Apply the transformation as a rank-2 update: */
/* A := A - v * w' - w * v' */
z__1.r = -1., z__1.i = -0.;
zher2_(uplo, &i__, &z__1, &a[(i__ + 1) * a_dim1 + 1], &c__1, &
tau[1], &c__1, &a[a_offset], lda);
} else {
i__1 = i__ + i__ * a_dim1;
i__2 = i__ + i__ * a_dim1;
d__1 = a[i__2].r;
a[i__1].r = d__1, a[i__1].i = 0.;
}
i__1 = i__ + (i__ + 1) * a_dim1;
i__2 = i__;
a[i__1].r = e[i__2], a[i__1].i = 0.;
i__1 = i__ + 1;
i__2 = i__ + 1 + (i__ + 1) * a_dim1;
d__[i__1] = a[i__2].r;
i__1 = i__;
tau[i__1].r = taui.r, tau[i__1].i = taui.i;
/* L10: */
}
i__1 = a_dim1 + 1;
d__[1] = a[i__1].r;
} else {
/* Reduce the lower triangle of A */
i__1 = a_dim1 + 1;
i__2 = a_dim1 + 1;
d__1 = a[i__2].r;
a[i__1].r = d__1, a[i__1].i = 0.;
i__1 = *n - 1;
for (i__ = 1; i__ <= i__1; ++i__) {
/* Generate elementary reflector H(i) = I - tau * v * v' */
/* to annihilate A(i+2:n,i) */
i__2 = i__ + 1 + i__ * a_dim1;
alpha.r = a[i__2].r, alpha.i = a[i__2].i;
i__2 = *n - i__;
/* Computing MIN */
i__3 = i__ + 2;
zlarfg_(&i__2, &alpha, &a[MIN(i__3, *n)+ i__ * a_dim1], &c__1, &
taui);
i__2 = i__;
e[i__2] = alpha.r;
if (taui.r != 0. || taui.i != 0.) {
/* Apply H(i) from both sides to A(i+1:n,i+1:n) */
i__2 = i__ + 1 + i__ * a_dim1;
a[i__2].r = 1., a[i__2].i = 0.;
/* Compute x := tau * A * v storing y in TAU(i:n-1) */
i__2 = *n - i__;
zhemv_(uplo, &i__2, &taui, &a[i__ + 1 + (i__ + 1) * a_dim1],
lda, &a[i__ + 1 + i__ * a_dim1], &c__1, &c_b2, &tau[
i__], &c__1);
/* Compute w := x - 1/2 * tau * (x'*v) * v */
z__3.r = -.5, z__3.i = -0.;
z__2.r = z__3.r * taui.r - z__3.i * taui.i, z__2.i = z__3.r *
taui.i + z__3.i * taui.r;
i__2 = *n - i__;
zdotc_(&z__4, &i__2, &tau[i__], &c__1, &a[i__ + 1 + i__ *
a_dim1], &c__1);
z__1.r = z__2.r * z__4.r - z__2.i * z__4.i, z__1.i = z__2.r *
z__4.i + z__2.i * z__4.r;
alpha.r = z__1.r, alpha.i = z__1.i;
i__2 = *n - i__;
zaxpy_(&i__2, &alpha, &a[i__ + 1 + i__ * a_dim1], &c__1, &tau[
i__], &c__1);
/* Apply the transformation as a rank-2 update: */
/* A := A - v * w' - w * v' */
i__2 = *n - i__;
z__1.r = -1., z__1.i = -0.;
zher2_(uplo, &i__2, &z__1, &a[i__ + 1 + i__ * a_dim1], &c__1,
&tau[i__], &c__1, &a[i__ + 1 + (i__ + 1) * a_dim1],
lda);
} else {
i__2 = i__ + 1 + (i__ + 1) * a_dim1;
i__3 = i__ + 1 + (i__ + 1) * a_dim1;
d__1 = a[i__3].r;
a[i__2].r = d__1, a[i__2].i = 0.;
}
i__2 = i__ + 1 + i__ * a_dim1;
i__3 = i__;
a[i__2].r = e[i__3], a[i__2].i = 0.;
i__2 = i__;
i__3 = i__ + i__ * a_dim1;
d__[i__2] = a[i__3].r;
i__2 = i__;
tau[i__2].r = taui.r, tau[i__2].i = taui.i;
/* L20: */
}
i__1 = *n;
i__2 = *n + *n * a_dim1;
d__[i__1] = a[i__2].r;
}
return 0;
/* End of ZHETD2 */
} /* zhetd2_ */
