/* zggesx.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 doublecomplex c_b1 = {0.,0.}; static doublecomplex c_b2 = {1.,0.}; static integer c__1 = 1; static integer c__0 = 0; static integer c_n1 = -1; /* Subroutine */ int zggesx_(char *jobvsl, char *jobvsr, char *sort, L_fp selctg, char *sense, integer *n, doublecomplex *a, integer *lda, doublecomplex *b, integer *ldb, integer *sdim, doublecomplex *alpha, doublecomplex *beta, doublecomplex *vsl, integer *ldvsl, doublecomplex *vsr, integer *ldvsr, doublereal *rconde, doublereal * rcondv, doublecomplex *work, integer *lwork, doublereal *rwork, integer *iwork, integer *liwork, logical *bwork, integer *info) { /* System generated locals */ integer a_dim1, a_offset, b_dim1, b_offset, vsl_dim1, vsl_offset, vsr_dim1, vsr_offset, i__1, i__2; /* Builtin functions */ double sqrt(doublereal); /* Local variables */ integer i__; doublereal pl, pr, dif[2]; integer ihi, ilo; doublereal eps; integer ijob; doublereal anrm, bnrm; integer ierr, itau, iwrk, lwrk; extern logical lsame_(char *, char *); integer ileft, icols; logical cursl, ilvsl, ilvsr; integer irwrk, irows; extern /* Subroutine */ int dlabad_(doublereal *, doublereal *); extern doublereal dlamch_(char *); extern /* Subroutine */ int zggbak_(char *, char *, integer *, integer *, integer *, doublereal *, doublereal *, integer *, doublecomplex *, integer *, integer *), zggbal_(char *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, integer * , integer *, doublereal *, doublereal *, doublereal *, integer *); logical ilascl, ilbscl; extern /* Subroutine */ int xerbla_(char *, integer *); extern integer ilaenv_(integer *, char *, char *, integer *, integer *, integer *, integer *); extern doublereal zlange_(char *, integer *, integer *, doublecomplex *, integer *, doublereal *); doublereal bignum; integer ijobvl, iright; extern /* Subroutine */ int zgghrd_(char *, char *, integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, integer * ), zlascl_(char *, integer *, integer *, doublereal *, doublereal *, integer *, integer *, doublecomplex *, integer *, integer *); integer ijobvr; logical wantsb; integer liwmin; logical wantse, lastsl; doublereal anrmto, bnrmto; extern /* Subroutine */ int zgeqrf_(integer *, integer *, doublecomplex *, integer *, doublecomplex *, doublecomplex *, integer *, integer * ); integer maxwrk; logical wantsn; integer minwrk; doublereal smlnum; extern /* Subroutine */ int zhgeqz_(char *, char *, char *, integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, doublecomplex *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublereal *, integer *), zlacpy_(char *, integer *, integer *, doublecomplex *, integer *, doublecomplex * , integer *), zlaset_(char *, integer *, integer *, doublecomplex *, doublecomplex *, doublecomplex *, integer *); logical wantst, lquery, wantsv; extern /* Subroutine */ int ztgsen_(integer *, logical *, logical *, logical *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, doublecomplex *, doublecomplex *, integer *, doublecomplex *, integer *, integer *, doublereal *, doublereal *, doublereal *, doublecomplex *, integer *, integer *, integer *, integer *), zungqr_(integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, doublecomplex *, integer *, integer *), zunmqr_(char *, char *, integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, doublecomplex *, integer *, doublecomplex *, integer *, integer *); /* -- LAPACK driver routine (version 3.2) -- */ /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ /* November 2006 */ /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* .. Function Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* ZGGESX computes for a pair of N-by-N complex nonsymmetric matrices */ /* (A,B), the generalized eigenvalues, the complex Schur form (S,T), */ /* and, optionally, the left and/or right matrices of Schur vectors (VSL */ /* and VSR). This gives the generalized Schur factorization */ /* (A,B) = ( (VSL) S (VSR)**H, (VSL) T (VSR)**H ) */ /* where (VSR)**H is the conjugate-transpose of VSR. */ /* Optionally, it also orders the eigenvalues so that a selected cluster */ /* of eigenvalues appears in the leading diagonal blocks of the upper */ /* triangular matrix S and the upper triangular matrix T; computes */ /* a reciprocal condition number for the average of the selected */ /* eigenvalues (RCONDE); and computes a reciprocal condition number for */ /* the right and left deflating subspaces corresponding to the selected */ /* eigenvalues (RCONDV). The leading columns of VSL and VSR then form */ /* an orthonormal basis for the corresponding left and right eigenspaces */ /* (deflating subspaces). */ /* A generalized eigenvalue for a pair of matrices (A,B) is a scalar w */ /* or a ratio alpha/beta = w, such that A - w*B is singular. It is */ /* usually represented as the pair (alpha,beta), as there is a */ /* reasonable interpretation for beta=0 or for both being zero. */ /* A pair of matrices (S,T) is in generalized complex Schur form if T is */ /* upper triangular with non-negative diagonal and S is upper */ /* triangular. */ /* Arguments */ /* ========= */ /* JOBVSL (input) CHARACTER*1 */ /* = 'N': do not compute the left Schur vectors; */ /* = 'V': compute the left Schur vectors. */ /* JOBVSR (input) CHARACTER*1 */ /* = 'N': do not compute the right Schur vectors; */ /* = 'V': compute the right Schur vectors. */ /* SORT (input) CHARACTER*1 */ /* Specifies whether or not to order the eigenvalues on the */ /* diagonal of the generalized Schur form. */ /* = 'N': Eigenvalues are not ordered; */ /* = 'S': Eigenvalues are ordered (see SELCTG). */ /* SELCTG (external procedure) LOGICAL FUNCTION of two COMPLEX*16 arguments */ /* SELCTG must be declared EXTERNAL in the calling subroutine. */ /* If SORT = 'N', SELCTG is not referenced. */ /* If SORT = 'S', SELCTG is used to select eigenvalues to sort */ /* to the top left of the Schur form. */ /* Note that a selected complex eigenvalue may no longer satisfy */ /* SELCTG(ALPHA(j),BETA(j)) = .TRUE. after ordering, since */ /* ordering may change the value of complex eigenvalues */ /* (especially if the eigenvalue is ill-conditioned), in this */ /* case INFO is set to N+3 see INFO below). */ /* SENSE (input) CHARACTER*1 */ /* Determines which reciprocal condition numbers are computed. */ /* = 'N' : None are computed; */ /* = 'E' : Computed for average of selected eigenvalues only; */ /* = 'V' : Computed for selected deflating subspaces only; */ /* = 'B' : Computed for both. */ /* If SENSE = 'E', 'V', or 'B', SORT must equal 'S'. */ /* N (input) INTEGER */ /* The order of the matrices A, B, VSL, and VSR. N >= 0. */ /* A (input/output) COMPLEX*16 array, dimension (LDA, N) */ /* On entry, the first of the pair of matrices. */ /* On exit, A has been overwritten by its generalized Schur */ /* form S. */ /* LDA (input) INTEGER */ /* The leading dimension of A. LDA >= max(1,N). */ /* B (input/output) COMPLEX*16 array, dimension (LDB, N) */ /* On entry, the second of the pair of matrices. */ /* On exit, B has been overwritten by its generalized Schur */ /* form T. */ /* LDB (input) INTEGER */ /* The leading dimension of B. LDB >= max(1,N). */ /* SDIM (output) INTEGER */ /* If SORT = 'N', SDIM = 0. */ /* If SORT = 'S', SDIM = number of eigenvalues (after sorting) */ /* for which SELCTG is true. */ /* ALPHA (output) COMPLEX*16 array, dimension (N) */ /* BETA (output) COMPLEX*16 array, dimension (N) */ /* On exit, ALPHA(j)/BETA(j), j=1,...,N, will be the */ /* generalized eigenvalues. ALPHA(j) and BETA(j),j=1,...,N are */ /* the diagonals of the complex Schur form (S,T). BETA(j) will */ /* be non-negative real. */ /* Note: the quotients ALPHA(j)/BETA(j) may easily over- or */ /* underflow, and BETA(j) may even be zero. Thus, the user */ /* should avoid naively computing the ratio alpha/beta. */ /* However, ALPHA will be always less than and usually */ /* comparable with norm(A) in magnitude, and BETA always less */ /* than and usually comparable with norm(B). */ /* VSL (output) COMPLEX*16 array, dimension (LDVSL,N) */ /* If JOBVSL = 'V', VSL will contain the left Schur vectors. */ /* Not referenced if JOBVSL = 'N'. */ /* LDVSL (input) INTEGER */ /* The leading dimension of the matrix VSL. LDVSL >=1, and */ /* if JOBVSL = 'V', LDVSL >= N. */ /* VSR (output) COMPLEX*16 array, dimension (LDVSR,N) */ /* If JOBVSR = 'V', VSR will contain the right Schur vectors. */ /* Not referenced if JOBVSR = 'N'. */ /* LDVSR (input) INTEGER */ /* The leading dimension of the matrix VSR. LDVSR >= 1, and */ /* if JOBVSR = 'V', LDVSR >= N. */ /* RCONDE (output) DOUBLE PRECISION array, dimension ( 2 ) */ /* If SENSE = 'E' or 'B', RCONDE(1) and RCONDE(2) contain the */ /* reciprocal condition numbers for the average of the selected */ /* eigenvalues. */ /* Not referenced if SENSE = 'N' or 'V'. */ /* RCONDV (output) DOUBLE PRECISION array, dimension ( 2 ) */ /* If SENSE = 'V' or 'B', RCONDV(1) and RCONDV(2) contain the */ /* reciprocal condition number for the selected deflating */ /* subspaces. */ /* Not referenced if SENSE = 'N' or 'E'. */ /* WORK (workspace/output) COMPLEX*16 array, dimension (MAX(1,LWORK)) */ /* On exit, if INFO = 0, WORK(1) returns the optimal LWORK. */ /* LWORK (input) INTEGER */ /* The dimension of the array WORK. */ /* If N = 0, LWORK >= 1, else if SENSE = 'E', 'V', or 'B', */ /* LWORK >= MAX(1,2*N,2*SDIM*(N-SDIM)), else */ /* LWORK >= MAX(1,2*N). Note that 2*SDIM*(N-SDIM) <= N*N/2. */ /* Note also that an error is only returned if */ /* LWORK < MAX(1,2*N), but if SENSE = 'E' or 'V' or 'B' this may */ /* not be large enough. */ /* If LWORK = -1, then a workspace query is assumed; the routine */ /* only calculates the bound on the optimal size of the WORK */ /* array and the minimum size of the IWORK array, returns these */ /* values as the first entries of the WORK and IWORK arrays, and */ /* no error message related to LWORK or LIWORK is issued by */ /* XERBLA. */ /* RWORK (workspace) DOUBLE PRECISION array, dimension ( 8*N ) */ /* Real workspace. */ /* IWORK (workspace/output) INTEGER array, dimension (MAX(1,LIWORK)) */ /* On exit, if INFO = 0, IWORK(1) returns the minimum LIWORK. */ /* LIWORK (input) INTEGER */ /* The dimension of the array IWORK. */ /* If SENSE = 'N' or N = 0, LIWORK >= 1, otherwise */ /* LIWORK >= N+2. */ /* If LIWORK = -1, then a workspace query is assumed; the */ /* routine only calculates the bound on the optimal size of the */ /* WORK array and the minimum size of the IWORK array, returns */ /* these values as the first entries of the WORK and IWORK */ /* arrays, and no error message related to LWORK or LIWORK is */ /* issued by XERBLA. */ /* BWORK (workspace) LOGICAL array, dimension (N) */ /* Not referenced if SORT = 'N'. */ /* INFO (output) INTEGER */ /* = 0: successful exit */ /* < 0: if INFO = -i, the i-th argument had an illegal value. */ /* = 1,...,N: */ /* The QZ iteration failed. (A,B) are not in Schur */ /* form, but ALPHA(j) and BETA(j) should be correct for */ /* j=INFO+1,...,N. */ /* > N: =N+1: other than QZ iteration failed in ZHGEQZ */ /* =N+2: after reordering, roundoff changed values of */ /* some complex eigenvalues so that leading */ /* eigenvalues in the Generalized Schur form no */ /* longer satisfy SELCTG=.TRUE. This could also */ /* be caused due to scaling. */ /* =N+3: reordering failed in ZTGSEN. */ /* ===================================================================== */ /* .. Parameters .. */ /* .. */ /* .. Local Scalars .. */ /* .. */ /* .. Local Arrays .. */ /* .. */ /* .. External Subroutines .. */ /* .. */ /* .. External Functions .. */ /* .. */ /* .. Intrinsic Functions .. */ /* .. */ /* .. Executable Statements .. */ /* Decode the input arguments */ /* Parameter adjustments */ a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; b_dim1 = *ldb; b_offset = 1 + b_dim1; b -= b_offset; --alpha; --beta; vsl_dim1 = *ldvsl; vsl_offset = 1 + vsl_dim1; vsl -= vsl_offset; vsr_dim1 = *ldvsr; vsr_offset = 1 + vsr_dim1; vsr -= vsr_offset; --rconde; --rcondv; --work; --rwork; --iwork; --bwork; /* Function Body */ if (lsame_(jobvsl, "N")) { ijobvl = 1; ilvsl = FALSE_; } else if (lsame_(jobvsl, "V")) { ijobvl = 2; ilvsl = TRUE_; } else { ijobvl = -1; ilvsl = FALSE_; } if (lsame_(jobvsr, "N")) { ijobvr = 1; ilvsr = FALSE_; } else if (lsame_(jobvsr, "V")) { ijobvr = 2; ilvsr = TRUE_; } else { ijobvr = -1; ilvsr = FALSE_; } wantst = lsame_(sort, "S"); wantsn = lsame_(sense, "N"); wantse = lsame_(sense, "E"); wantsv = lsame_(sense, "V"); wantsb = lsame_(sense, "B"); lquery = *lwork == -1 || *liwork == -1; if (wantsn) { ijob = 0; } else if (wantse) { ijob = 1; } else if (wantsv) { ijob = 2; } else if (wantsb) { ijob = 4; } /* Test the input arguments */ *info = 0; if (ijobvl <= 0) { *info = -1; } else if (ijobvr <= 0) { *info = -2; } else if (! wantst && ! lsame_(sort, "N")) { *info = -3; } else if (! (wantsn || wantse || wantsv || wantsb) || ! wantst && ! wantsn) { *info = -5; } else if (*n < 0) { *info = -6; } else if (*lda < max(1,*n)) { *info = -8; } else if (*ldb < max(1,*n)) { *info = -10; } else if (*ldvsl < 1 || ilvsl && *ldvsl < *n) { *info = -15; } else if (*ldvsr < 1 || ilvsr && *ldvsr < *n) { *info = -17; } /* Compute workspace */ /* (Note: Comments in the code beginning "Workspace:" describe the */ /* minimal amount of workspace needed at that point in the code, */ /* as well as the preferred amount for good performance. */ /* NB refers to the optimal block size for the immediately */ /* following subroutine, as returned by ILAENV.) */ if (*info == 0) { if (*n > 0) { minwrk = *n << 1; maxwrk = *n * (ilaenv_(&c__1, "ZGEQRF", " ", n, &c__1, n, &c__0) + 1); /* Computing MAX */ i__1 = maxwrk, i__2 = *n * (ilaenv_(&c__1, "ZUNMQR", " ", n, & c__1, n, &c_n1) + 1); maxwrk = max(i__1,i__2); if (ilvsl) { /* Computing MAX */ i__1 = maxwrk, i__2 = *n * (ilaenv_(&c__1, "ZUNGQR", " ", n, & c__1, n, &c_n1) + 1); maxwrk = max(i__1,i__2); } lwrk = maxwrk; if (ijob >= 1) { /* Computing MAX */ i__1 = lwrk, i__2 = *n * *n / 2; lwrk = max(i__1,i__2); } } else { minwrk = 1; maxwrk = 1; lwrk = 1; } work[1].r = (doublereal) lwrk, work[1].i = 0.; if (wantsn || *n == 0) { liwmin = 1; } else { liwmin = *n + 2; } iwork[1] = liwmin; if (*lwork < minwrk && ! lquery) { *info = -21; } else if (*liwork < liwmin && ! lquery) { *info = -24; } } if (*info != 0) { i__1 = -(*info); xerbla_("ZGGESX", &i__1); return 0; } else if (lquery) { return 0; } /* Quick return if possible */ if (*n == 0) { *sdim = 0; return 0; } /* Get machine constants */ eps = dlamch_("P"); smlnum = dlamch_("S"); bignum = 1. / smlnum; dlabad_(&smlnum, &bignum); smlnum = sqrt(smlnum) / eps; bignum = 1. / smlnum; /* Scale A if max element outside range [SMLNUM,BIGNUM] */ anrm = zlange_("M", n, n, &a[a_offset], lda, &rwork[1]); ilascl = FALSE_; if (anrm > 0. && anrm < smlnum) { anrmto = smlnum; ilascl = TRUE_; } else if (anrm > bignum) { anrmto = bignum; ilascl = TRUE_; } if (ilascl) { zlascl_("G", &c__0, &c__0, &anrm, &anrmto, n, n, &a[a_offset], lda, & ierr); } /* Scale B if max element outside range [SMLNUM,BIGNUM] */ bnrm = zlange_("M", n, n, &b[b_offset], ldb, &rwork[1]); ilbscl = FALSE_; if (bnrm > 0. && bnrm < smlnum) { bnrmto = smlnum; ilbscl = TRUE_; } else if (bnrm > bignum) { bnrmto = bignum; ilbscl = TRUE_; } if (ilbscl) { zlascl_("G", &c__0, &c__0, &bnrm, &bnrmto, n, n, &b[b_offset], ldb, & ierr); } /* Permute the matrix to make it more nearly triangular */ /* (Real Workspace: need 6*N) */ ileft = 1; iright = *n + 1; irwrk = iright + *n; zggbal_("P", n, &a[a_offset], lda, &b[b_offset], ldb, &ilo, &ihi, &rwork[ ileft], &rwork[iright], &rwork[irwrk], &ierr); /* Reduce B to triangular form (QR decomposition of B) */ /* (Complex Workspace: need N, prefer N*NB) */ irows = ihi + 1 - ilo; icols = *n + 1 - ilo; itau = 1; iwrk = itau + irows; i__1 = *lwork + 1 - iwrk; zgeqrf_(&irows, &icols, &b[ilo + ilo * b_dim1], ldb, &work[itau], &work[ iwrk], &i__1, &ierr); /* Apply the unitary transformation to matrix A */ /* (Complex Workspace: need N, prefer N*NB) */ i__1 = *lwork + 1 - iwrk; zunmqr_("L", "C", &irows, &icols, &irows, &b[ilo + ilo * b_dim1], ldb, & work[itau], &a[ilo + ilo * a_dim1], lda, &work[iwrk], &i__1, & ierr); /* Initialize VSL */ /* (Complex Workspace: need N, prefer N*NB) */ if (ilvsl) { zlaset_("Full", n, n, &c_b1, &c_b2, &vsl[vsl_offset], ldvsl); if (irows > 1) { i__1 = irows - 1; i__2 = irows - 1; zlacpy_("L", &i__1, &i__2, &b[ilo + 1 + ilo * b_dim1], ldb, &vsl[ ilo + 1 + ilo * vsl_dim1], ldvsl); } i__1 = *lwork + 1 - iwrk; zungqr_(&irows, &irows, &irows, &vsl[ilo + ilo * vsl_dim1], ldvsl, & work[itau], &work[iwrk], &i__1, &ierr); } /* Initialize VSR */ if (ilvsr) { zlaset_("Full", n, n, &c_b1, &c_b2, &vsr[vsr_offset], ldvsr); } /* Reduce to generalized Hessenberg form */ /* (Workspace: none needed) */ zgghrd_(jobvsl, jobvsr, n, &ilo, &ihi, &a[a_offset], lda, &b[b_offset], ldb, &vsl[vsl_offset], ldvsl, &vsr[vsr_offset], ldvsr, &ierr); *sdim = 0; /* Perform QZ algorithm, computing Schur vectors if desired */ /* (Complex Workspace: need N) */ /* (Real Workspace: need N) */ iwrk = itau; i__1 = *lwork + 1 - iwrk; zhgeqz_("S", jobvsl, jobvsr, n, &ilo, &ihi, &a[a_offset], lda, &b[ b_offset], ldb, &alpha[1], &beta[1], &vsl[vsl_offset], ldvsl, & vsr[vsr_offset], ldvsr, &work[iwrk], &i__1, &rwork[irwrk], &ierr); if (ierr != 0) { if (ierr > 0 && ierr <= *n) { *info = ierr; } else if (ierr > *n && ierr <= *n << 1) { *info = ierr - *n; } else { *info = *n + 1; } goto L40; } /* Sort eigenvalues ALPHA/BETA and compute the reciprocal of */ /* condition number(s) */ if (wantst) { /* Undo scaling on eigenvalues before SELCTGing */ if (ilascl) { zlascl_("G", &c__0, &c__0, &anrmto, &anrm, n, &c__1, &alpha[1], n, &ierr); } if (ilbscl) { zlascl_("G", &c__0, &c__0, &bnrmto, &bnrm, n, &c__1, &beta[1], n, &ierr); } /* Select eigenvalues */ i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { bwork[i__] = (*selctg)(&alpha[i__], &beta[i__]); /* L10: */ } /* Reorder eigenvalues, transform Generalized Schur vectors, and */ /* compute reciprocal condition numbers */ /* (Complex Workspace: If IJOB >= 1, need MAX(1, 2*SDIM*(N-SDIM)) */ /* otherwise, need 1 ) */ i__1 = *lwork - iwrk + 1; ztgsen_(&ijob, &ilvsl, &ilvsr, &bwork[1], n, &a[a_offset], lda, &b[ b_offset], ldb, &alpha[1], &beta[1], &vsl[vsl_offset], ldvsl, &vsr[vsr_offset], ldvsr, sdim, &pl, &pr, dif, &work[iwrk], & i__1, &iwork[1], liwork, &ierr); if (ijob >= 1) { /* Computing MAX */ i__1 = maxwrk, i__2 = (*sdim << 1) * (*n - *sdim); maxwrk = max(i__1,i__2); } if (ierr == -21) { /* not enough complex workspace */ *info = -21; } else { if (ijob == 1 || ijob == 4) { rconde[1] = pl; rconde[2] = pr; } if (ijob == 2 || ijob == 4) { rcondv[1] = dif[0]; rcondv[2] = dif[1]; } if (ierr == 1) { *info = *n + 3; } } } /* Apply permutation to VSL and VSR */ /* (Workspace: none needed) */ if (ilvsl) { zggbak_("P", "L", n, &ilo, &ihi, &rwork[ileft], &rwork[iright], n, & vsl[vsl_offset], ldvsl, &ierr); } if (ilvsr) { zggbak_("P", "R", n, &ilo, &ihi, &rwork[ileft], &rwork[iright], n, & vsr[vsr_offset], ldvsr, &ierr); } /* Undo scaling */ if (ilascl) { zlascl_("U", &c__0, &c__0, &anrmto, &anrm, n, n, &a[a_offset], lda, & ierr); zlascl_("G", &c__0, &c__0, &anrmto, &anrm, n, &c__1, &alpha[1], n, & ierr); } if (ilbscl) { zlascl_("U", &c__0, &c__0, &bnrmto, &bnrm, n, n, &b[b_offset], ldb, & ierr); zlascl_("G", &c__0, &c__0, &bnrmto, &bnrm, n, &c__1, &beta[1], n, & ierr); } if (wantst) { /* Check if reordering is correct */ lastsl = TRUE_; *sdim = 0; i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { cursl = (*selctg)(&alpha[i__], &beta[i__]); if (cursl) { ++(*sdim); } if (cursl && ! lastsl) { *info = *n + 2; } lastsl = cursl; /* L30: */ } } L40: work[1].r = (doublereal) maxwrk, work[1].i = 0.; iwork[1] = liwmin; return 0; /* End of ZGGESX */ } /* zggesx_ */