ggbak - ggbak: back-transform eigvec

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subroutinecggbak(characterjob,characterside,integern,integerilo,integerihi,real,dimension(*)lscale,real,dimension(*)rscale,integerm,complex,dimension(ldv,*)v,integerldv,integerinfo)CGGBAKPurpose: CGGBAK forms the right or left eigenvectors of a complex generalized eigenvalue problem A*x = lambda*B*x, by backward transformation on the computed eigenvectors of the balanced pair of matrices output by CGGBAL. ParametersJOB JOB is CHARACTER*1 Specifies the type of backward transformation required: = 'N': do nothing, return immediately; = 'P': do backward transformation for permutation only; = 'S': do backward transformation for scaling only; = 'B': do backward transformations for both permutation and scaling. JOB must be the same as the argument JOB supplied to CGGBAL. SIDE SIDE is CHARACTER*1 = 'R': V contains right eigenvectors; = 'L': V contains left eigenvectors. N N is INTEGER The number of rows of the matrix V. N >= 0. ILO ILO is INTEGER IHI IHI is INTEGER The integers ILO and IHI determined by CGGBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. LSCALE LSCALE is REAL array, dimension (N) Details of the permutations and/or scaling factors applied to the left side of A and B, as returned by CGGBAL. RSCALE RSCALE is REAL array, dimension (N) Details of the permutations and/or scaling factors applied to the right side of A and B, as returned by CGGBAL. M M is INTEGER The number of columns of the matrix V. M >= 0. V V is COMPLEX array, dimension (LDV,M) On entry, the matrix of right or left eigenvectors to be transformed, as returned by CTGEVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the matrix V. LDV >= max(1,N). INFO INFO is INTEGER = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: See R.C. Ward, Balancing the generalized eigenvalue problem, SIAM J. Sci. Stat. Comp. 2 (1981), 141-152. subroutinedggbak(characterjob,characterside,integern,integerilo,integerihi,doubleprecision,dimension(*)lscale,doubleprecision,dimension(*)rscale,integerm,doubleprecision,dimension(ldv,*)v,integerldv,integerinfo)DGGBAKPurpose: DGGBAK forms the right or left eigenvectors of a real generalized eigenvalue problem A*x = lambda*B*x, by backward transformation on the computed eigenvectors of the balanced pair of matrices output by DGGBAL. ParametersJOB JOB is CHARACTER*1 Specifies the type of backward transformation required: = 'N': do nothing, return immediately; = 'P': do backward transformation for permutation only; = 'S': do backward transformation for scaling only; = 'B': do backward transformations for both permutation and scaling. JOB must be the same as the argument JOB supplied to DGGBAL. SIDE SIDE is CHARACTER*1 = 'R': V contains right eigenvectors; = 'L': V contains left eigenvectors. N N is INTEGER The number of rows of the matrix V. N >= 0. ILO ILO is INTEGER IHI IHI is INTEGER The integers ILO and IHI determined by DGGBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. LSCALE LSCALE is DOUBLE PRECISION array, dimension (N) Details of the permutations and/or scaling factors applied to the left side of A and B, as returned by DGGBAL. RSCALE RSCALE is DOUBLE PRECISION array, dimension (N) Details of the permutations and/or scaling factors applied to the right side of A and B, as returned by DGGBAL. M M is INTEGER The number of columns of the matrix V. M >= 0. V V is DOUBLE PRECISION array, dimension (LDV,M) On entry, the matrix of right or left eigenvectors to be transformed, as returned by DTGEVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the matrix V. LDV >= max(1,N). INFO INFO is INTEGER = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: See R.C. Ward, Balancing the generalized eigenvalue problem, SIAM J. Sci. Stat. Comp. 2 (1981), 141-152. subroutinesggbak(characterjob,characterside,integern,integerilo,integerihi,real,dimension(*)lscale,real,dimension(*)rscale,integerm,real,dimension(ldv,*)v,integerldv,integerinfo)SGGBAKPurpose: SGGBAK forms the right or left eigenvectors of a real generalized eigenvalue problem A*x = lambda*B*x, by backward transformation on the computed eigenvectors of the balanced pair of matrices output by SGGBAL. ParametersJOB JOB is CHARACTER*1 Specifies the type of backward transformation required: = 'N': do nothing, return immediately; = 'P': do backward transformation for permutation only; = 'S': do backward transformation for scaling only; = 'B': do backward transformations for both permutation and scaling. JOB must be the same as the argument JOB supplied to SGGBAL. SIDE SIDE is CHARACTER*1 = 'R': V contains right eigenvectors; = 'L': V contains left eigenvectors. N N is INTEGER The number of rows of the matrix V. N >= 0. ILO ILO is INTEGER IHI IHI is INTEGER The integers ILO and IHI determined by SGGBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. LSCALE LSCALE is REAL array, dimension (N) Details of the permutations and/or scaling factors applied to the left side of A and B, as returned by SGGBAL. RSCALE RSCALE is REAL array, dimension (N) Details of the permutations and/or scaling factors applied to the right side of A and B, as returned by SGGBAL. M M is INTEGER The number of columns of the matrix V. M >= 0. V V is REAL array, dimension (LDV,M) On entry, the matrix of right or left eigenvectors to be transformed, as returned by STGEVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the matrix V. LDV >= max(1,N). INFO INFO is INTEGER = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: See R.C. Ward, Balancing the generalized eigenvalue problem, SIAM J. Sci. Stat. Comp. 2 (1981), 141-152. subroutinezggbak(characterjob,characterside,integern,integerilo,integerihi,doubleprecision,dimension(*)lscale,doubleprecision,dimension(*)rscale,integerm,complex*16,dimension(ldv,*)v,integerldv,integerinfo)ZGGBAKPurpose: ZGGBAK forms the right or left eigenvectors of a complex generalized eigenvalue problem A*x = lambda*B*x, by backward transformation on the computed eigenvectors of the balanced pair of matrices output by ZGGBAL. ParametersJOB JOB is CHARACTER*1 Specifies the type of backward transformation required: = 'N': do nothing, return immediately; = 'P': do backward transformation for permutation only; = 'S': do backward transformation for scaling only; = 'B': do backward transformations for both permutation and scaling. JOB must be the same as the argument JOB supplied to ZGGBAL. SIDE SIDE is CHARACTER*1 = 'R': V contains right eigenvectors; = 'L': V contains left eigenvectors. N N is INTEGER The number of rows of the matrix V. N >= 0. ILO ILO is INTEGER IHI IHI is INTEGER The integers ILO and IHI determined by ZGGBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. LSCALE LSCALE is DOUBLE PRECISION array, dimension (N) Details of the permutations and/or scaling factors applied to the left side of A and B, as returned by ZGGBAL. RSCALE RSCALE is DOUBLE PRECISION array, dimension (N) Details of the permutations and/or scaling factors applied to the right side of A and B, as returned by ZGGBAL. M M is INTEGER The number of columns of the matrix V. M >= 0. V V is COMPLEX*16 array, dimension (LDV,M) On entry, the matrix of right or left eigenvectors to be transformed, as returned by ZTGEVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the matrix V. LDV >= max(1,N). INFO INFO is INTEGER = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: See R.C. Ward, Balancing the generalized eigenvalue problem, SIAM J. Sci. Stat. Comp. 2 (1981), 141-152.

ggbak - ggbak: back-transform eigvec

Functions subroutine cggbak (job, side, n, ilo, ihi, lscale, rscale, m, v, ldv, info) CGGBAK subroutine dggbak (job, side, n, ilo, ihi, lscale, rscale, m, v, ldv, info) DGGBAK subroutine sggbak (job, side, n, ilo, ihi, lscale, rscale, m, v, ldv, info) SGGBAK subroutine zggbak (job, side, n, ilo, ihi, lscale, rscale, m, v, ldv, info) ZGGBAK