gebak - gebak: back-transform eigvec

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subroutinecgebak(characterjob,characterside,integern,integerilo,integerihi,real,dimension(*)scale,integerm,complex,dimension(ldv,*)v,integerldv,integerinfo)CGEBAKPurpose: CGEBAK forms the right or left eigenvectors of a complex general matrix by backward transformation on the computed eigenvectors of the balanced matrix output by CGEBAL. 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 CGEBAL. 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 CGEBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. SCALE SCALE is REAL array, dimension (N) Details of the permutation and scaling factors, as returned by CGEBAL. 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 CHSEIN or CTREVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the array 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. subroutinedgebak(characterjob,characterside,integern,integerilo,integerihi,doubleprecision,dimension(*)scale,integerm,doubleprecision,dimension(ldv,*)v,integerldv,integerinfo)DGEBAKPurpose: DGEBAK forms the right or left eigenvectors of a real general matrix by backward transformation on the computed eigenvectors of the balanced matrix output by DGEBAL. 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 DGEBAL. 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 DGEBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. SCALE SCALE is DOUBLE PRECISION array, dimension (N) Details of the permutation and scaling factors, as returned by DGEBAL. 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 DHSEIN or DTREVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the array 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. subroutinesgebak(characterjob,characterside,integern,integerilo,integerihi,real,dimension(*)scale,integerm,real,dimension(ldv,*)v,integerldv,integerinfo)SGEBAKPurpose: SGEBAK forms the right or left eigenvectors of a real general matrix by backward transformation on the computed eigenvectors of the balanced matrix output by SGEBAL. 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 SGEBAL. 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 SGEBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. SCALE SCALE is REAL array, dimension (N) Details of the permutation and scaling factors, as returned by SGEBAL. 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 SHSEIN or STREVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the array 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. subroutinezgebak(characterjob,characterside,integern,integerilo,integerihi,doubleprecision,dimension(*)scale,integerm,complex*16,dimension(ldv,*)v,integerldv,integerinfo)ZGEBAKPurpose: ZGEBAK forms the right or left eigenvectors of a complex general matrix by backward transformation on the computed eigenvectors of the balanced matrix output by ZGEBAL. 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 ZGEBAL. 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 ZGEBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. SCALE SCALE is DOUBLE PRECISION array, dimension (N) Details of the permutation and scaling factors, as returned by ZGEBAL. 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 ZHSEIN or ZTREVC. On exit, V is overwritten by the transformed eigenvectors. LDV LDV is INTEGER The leading dimension of the array 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.

gebak - gebak: back-transform eigvec

Functions subroutine cgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info) CGEBAK subroutine dgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info) DGEBAK subroutine sgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info) SGEBAK subroutine zgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info) ZGEBAK