/* clarfy.f -- translated by f2c (version 20061008). 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 */ #include "f2c.h" #include "blaswrap.h" /* Table of constant values */ static complex c_b1 = {1.f,0.f}; static complex c_b2 = {0.f,0.f}; static integer c__1 = 1; /* Subroutine */ int clarfy_(char *uplo, integer *n, complex *v, integer * incv, complex *tau, complex *c__, integer *ldc, complex *work) { /* System generated locals */ integer c_dim1, c_offset; complex q__1, q__2, q__3, q__4; /* Local variables */ extern /* Subroutine */ int cher2_(char *, integer *, complex *, complex * , integer *, complex *, integer *, complex *, integer *); complex alpha; extern /* Complex */ VOID cdotc_(complex *, integer *, complex *, integer *, complex *, integer *); extern /* Subroutine */ int chemv_(char *, integer *, complex *, complex * , integer *, complex *, integer *, complex *, complex *, integer * ), caxpy_(integer *, complex *, complex *, integer *, complex *, integer *); /* -- LAPACK auxiliary test routine (version 3.1) -- */ /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ /* November 2006 */ /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* CLARFY applies an elementary reflector, or Householder matrix, H, */ /* to an n x n Hermitian matrix C, from both the left and the right. */ /* H is represented in the form */ /* H = I - tau * v * v' */ /* where tau is a scalar and v is a vector. */ /* If tau is zero, then H is taken to be the unit matrix. */ /* Arguments */ /* ========= */ /* UPLO (input) CHARACTER*1 */ /* Specifies whether the upper or lower triangular part of the */ /* Hermitian matrix C is stored. */ /* = 'U': Upper triangle */ /* = 'L': Lower triangle */ /* N (input) INTEGER */ /* The number of rows and columns of the matrix C. N >= 0. */ /* V (input) COMPLEX array, dimension */ /* (1 + (N-1)*abs(INCV)) */ /* The vector v as described above. */ /* INCV (input) INTEGER */ /* The increment between successive elements of v. INCV must */ /* not be zero. */ /* TAU (input) COMPLEX */ /* The value tau as described above. */ /* C (input/output) COMPLEX array, dimension (LDC, N) */ /* On entry, the matrix C. */ /* On exit, C is overwritten by H * C * H'. */ /* LDC (input) INTEGER */ /* The leading dimension of the array C. LDC >= max( 1, N ). */ /* WORK (workspace) COMPLEX array, dimension (N) */ /* ===================================================================== */ /* .. Parameters .. */ /* .. */ /* .. Local Scalars .. */ /* .. */ /* .. External Subroutines .. */ /* .. */ /* .. External Functions .. */ /* .. */ /* .. Executable Statements .. */ /* Parameter adjustments */ --v; c_dim1 = *ldc; c_offset = 1 + c_dim1; c__ -= c_offset; --work; /* Function Body */ if (tau->r == 0.f && tau->i == 0.f) { return 0; } /* Form w:= C * v */ chemv_(uplo, n, &c_b1, &c__[c_offset], ldc, &v[1], incv, &c_b2, &work[1], &c__1); q__3.r = -.5f, q__3.i = -0.f; q__2.r = q__3.r * tau->r - q__3.i * tau->i, q__2.i = q__3.r * tau->i + q__3.i * tau->r; cdotc_(&q__4, n, &work[1], &c__1, &v[1], incv); q__1.r = q__2.r * q__4.r - q__2.i * q__4.i, q__1.i = q__2.r * q__4.i + q__2.i * q__4.r; alpha.r = q__1.r, alpha.i = q__1.i; caxpy_(n, &alpha, &v[1], incv, &work[1], &c__1); /* C := C - v * w' - w * v' */ q__1.r = -tau->r, q__1.i = -tau->i; cher2_(uplo, n, &q__1, &v[1], incv, &work[1], &c__1, &c__[c_offset], ldc); return 0; /* End of CLARFY */ } /* clarfy_ */