/* cla_gercond_x.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 integer c__1 = 1; doublereal cla_gercond_x__(char *trans, integer *n, complex *a, integer *lda, complex *af, integer *ldaf, integer *ipiv, complex *x, integer *info, complex *work, real *rwork, ftnlen trans_len) { /* System generated locals */ integer a_dim1, a_offset, af_dim1, af_offset, i__1, i__2, i__3, i__4; real ret_val, r__1, r__2; complex q__1, q__2; /* Builtin functions */ double r_imag(complex *); void c_div(complex *, complex *, complex *); /* Local variables */ integer i__, j; real tmp; integer kase; extern logical lsame_(char *, char *); integer isave[3]; real anorm; extern /* Subroutine */ int clacn2_(integer *, complex *, complex *, real *, integer *, integer *), xerbla_(char *, integer *), cgetrs_(char *, integer *, integer *, complex *, integer *, integer *, complex *, integer *, integer *); real ainvnm; logical notrans; /* -- LAPACK routine (version 3.2.1) -- */ /* -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and -- */ /* -- Jason Riedy of Univ. of California Berkeley. -- */ /* -- April 2009 -- */ /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */ /* -- Univ. of California Berkeley and NAG Ltd. -- */ /* .. */ /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* CLA_GERCOND_X computes the infinity norm condition number of */ /* op(A) * diag(X) where X is a COMPLEX vector. */ /* Arguments */ /* ========= */ /* TRANS (input) CHARACTER*1 */ /* Specifies the form of the system of equations: */ /* = 'N': A * X = B (No transpose) */ /* = 'T': A**T * X = B (Transpose) */ /* = 'C': A**H * X = B (Conjugate Transpose = Transpose) */ /* N (input) INTEGER */ /* The number of linear equations, i.e., the order of the */ /* matrix A. N >= 0. */ /* A (input) COMPLEX array, dimension (LDA,N) */ /* On entry, the N-by-N matrix A. */ /* LDA (input) INTEGER */ /* The leading dimension of the array A. LDA >= max(1,N). */ /* AF (input) COMPLEX array, dimension (LDAF,N) */ /* The factors L and U from the factorization */ /* A = P*L*U as computed by CGETRF. */ /* LDAF (input) INTEGER */ /* The leading dimension of the array AF. LDAF >= max(1,N). */ /* IPIV (input) INTEGER array, dimension (N) */ /* The pivot indices from the factorization A = P*L*U */ /* as computed by CGETRF; row i of the matrix was interchanged */ /* with row IPIV(i). */ /* X (input) COMPLEX array, dimension (N) */ /* The vector X in the formula op(A) * diag(X). */ /* INFO (output) INTEGER */ /* = 0: Successful exit. */ /* i > 0: The ith argument is invalid. */ /* WORK (input) COMPLEX array, dimension (2*N). */ /* Workspace. */ /* RWORK (input) REAL array, dimension (N). */ /* Workspace. */ /* ===================================================================== */ /* .. Local Scalars .. */ /* .. */ /* .. Local Arrays .. */ /* .. */ /* .. External Functions .. */ /* .. */ /* .. External Subroutines .. */ /* .. */ /* .. Intrinsic Functions .. */ /* .. */ /* .. Statement Functions .. */ /* .. */ /* .. Statement Function Definitions .. */ /* .. */ /* .. Executable Statements .. */ /* Parameter adjustments */ a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; af_dim1 = *ldaf; af_offset = 1 + af_dim1; af -= af_offset; --ipiv; --x; --work; --rwork; /* Function Body */ ret_val = 0.f; *info = 0; notrans = lsame_(trans, "N"); if (! notrans && ! lsame_(trans, "T") && ! lsame_( trans, "C")) { *info = -1; } else if (*n < 0) { *info = -2; } if (*info != 0) { i__1 = -(*info); xerbla_("CLA_GERCOND_X", &i__1); return ret_val; } /* Compute norm of op(A)*op2(C). */ anorm = 0.f; if (notrans) { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { tmp = 0.f; i__2 = *n; for (j = 1; j <= i__2; ++j) { i__3 = i__ + j * a_dim1; i__4 = j; q__2.r = a[i__3].r * x[i__4].r - a[i__3].i * x[i__4].i, q__2.i = a[i__3].r * x[i__4].i + a[i__3].i * x[i__4] .r; q__1.r = q__2.r, q__1.i = q__2.i; tmp += (r__1 = q__1.r, dabs(r__1)) + (r__2 = r_imag(&q__1), dabs(r__2)); } rwork[i__] = tmp; anorm = dmax(anorm,tmp); } } else { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { tmp = 0.f; i__2 = *n; for (j = 1; j <= i__2; ++j) { i__3 = j + i__ * a_dim1; i__4 = j; q__2.r = a[i__3].r * x[i__4].r - a[i__3].i * x[i__4].i, q__2.i = a[i__3].r * x[i__4].i + a[i__3].i * x[i__4] .r; q__1.r = q__2.r, q__1.i = q__2.i; tmp += (r__1 = q__1.r, dabs(r__1)) + (r__2 = r_imag(&q__1), dabs(r__2)); } rwork[i__] = tmp; anorm = dmax(anorm,tmp); } } /* Quick return if possible. */ if (*n == 0) { ret_val = 1.f; return ret_val; } else if (anorm == 0.f) { return ret_val; } /* Estimate the norm of inv(op(A)). */ ainvnm = 0.f; kase = 0; L10: clacn2_(n, &work[*n + 1], &work[1], &ainvnm, &kase, isave); if (kase != 0) { if (kase == 2) { /* Multiply by R. */ i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; i__3 = i__; i__4 = i__; q__1.r = rwork[i__4] * work[i__3].r, q__1.i = rwork[i__4] * work[i__3].i; work[i__2].r = q__1.r, work[i__2].i = q__1.i; } if (notrans) { cgetrs_("No transpose", n, &c__1, &af[af_offset], ldaf, &ipiv[ 1], &work[1], n, info); } else { cgetrs_("Conjugate transpose", n, &c__1, &af[af_offset], ldaf, &ipiv[1], &work[1], n, info); } /* Multiply by inv(X). */ i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; c_div(&q__1, &work[i__], &x[i__]); work[i__2].r = q__1.r, work[i__2].i = q__1.i; } } else { /* Multiply by inv(X'). */ i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; c_div(&q__1, &work[i__], &x[i__]); work[i__2].r = q__1.r, work[i__2].i = q__1.i; } if (notrans) { cgetrs_("Conjugate transpose", n, &c__1, &af[af_offset], ldaf, &ipiv[1], &work[1], n, info); } else { cgetrs_("No transpose", n, &c__1, &af[af_offset], ldaf, &ipiv[ 1], &work[1], n, info); } /* Multiply by R. */ i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; i__3 = i__; i__4 = i__; q__1.r = rwork[i__4] * work[i__3].r, q__1.i = rwork[i__4] * work[i__3].i; work[i__2].r = q__1.r, work[i__2].i = q__1.i; } } goto L10; } /* Compute the estimate of the reciprocal condition number. */ if (ainvnm != 0.f) { ret_val = 1.f / ainvnm; } return ret_val; } /* cla_gercond_x__ */