Provided by: liblapack-doc_3.12.0-3build1_all bug

NAME

       unbdb5 - {un,or}bdb5: step in uncsd2by1

SYNOPSIS

   Functions
       subroutine cunbdb5 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2, work, lwork,
           info)
           CUNBDB5
       subroutine dorbdb5 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2, work, lwork,
           info)
           DORBDB5
       subroutine sorbdb5 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2, work, lwork,
           info)
           SORBDB5
       subroutine zunbdb5 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2, work, lwork,
           info)
           ZUNBDB5

Detailed Description

Function Documentation

   subroutine cunbdb5 (integer m1, integer m2, integer n, complex, dimension(*) x1, integer
       incx1, complex, dimension(*) x2, integer incx2, complex, dimension(ldq1,*) q1, integer
       ldq1, complex, dimension(ldq2,*) q2, integer ldq2, complex, dimension(*) work, integer
       lwork, integer info)
       CUNBDB5

       Purpose:

            CUNBDB5 orthogonalizes the column vector
                 X = [ X1 ]
                     [ X2 ]
            with respect to the columns of
                 Q = [ Q1 ] .
                     [ Q2 ]
            The columns of Q must be orthonormal.

            If the projection is zero according to Kahan's 'twice is enough'
            criterion, then some other vector from the orthogonal complement
            is returned. This vector is chosen in an arbitrary but deterministic
            way.

       Parameters
           M1

                     M1 is INTEGER
                      The dimension of X1 and the number of rows in Q1. 0 <= M1.

           M2

                     M2 is INTEGER
                      The dimension of X2 and the number of rows in Q2. 0 <= M2.

           N

                     N is INTEGER
                      The number of columns in Q1 and Q2. 0 <= N.

           X1

                     X1 is COMPLEX array, dimension (M1)
                      On entry, the top part of the vector to be orthogonalized.
                      On exit, the top part of the projected vector.

           INCX1

                     INCX1 is INTEGER
                      Increment for entries of X1.

           X2

                     X2 is COMPLEX array, dimension (M2)
                      On entry, the bottom part of the vector to be
                      orthogonalized. On exit, the bottom part of the projected
                      vector.

           INCX2

                     INCX2 is INTEGER
                      Increment for entries of X2.

           Q1

                     Q1 is COMPLEX array, dimension (LDQ1, N)
                      The top part of the orthonormal basis matrix.

           LDQ1

                     LDQ1 is INTEGER
                      The leading dimension of Q1. LDQ1 >= M1.

           Q2

                     Q2 is COMPLEX array, dimension (LDQ2, N)
                      The bottom part of the orthonormal basis matrix.

           LDQ2

                     LDQ2 is INTEGER
                      The leading dimension of Q2. LDQ2 >= M2.

           WORK

                     WORK is COMPLEX array, dimension (LWORK)

           LWORK

                     LWORK is INTEGER
                      The dimension of the array WORK. LWORK >= 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.

   subroutine dorbdb5 (integer m1, integer m2, integer n, double precision, dimension(*) x1,
       integer incx1, double precision, dimension(*) x2, integer incx2, double precision,
       dimension(ldq1,*) q1, integer ldq1, double precision, dimension(ldq2,*) q2, integer ldq2,
       double precision, dimension(*) work, integer lwork, integer info)
       DORBDB5

       Purpose:

            DORBDB5 orthogonalizes the column vector
                 X = [ X1 ]
                     [ X2 ]
            with respect to the columns of
                 Q = [ Q1 ] .
                     [ Q2 ]
            The columns of Q must be orthonormal.

            If the projection is zero according to Kahan's 'twice is enough'
            criterion, then some other vector from the orthogonal complement
            is returned. This vector is chosen in an arbitrary but deterministic
            way.

       Parameters
           M1

                     M1 is INTEGER
                      The dimension of X1 and the number of rows in Q1. 0 <= M1.

           M2

                     M2 is INTEGER
                      The dimension of X2 and the number of rows in Q2. 0 <= M2.

           N

                     N is INTEGER
                      The number of columns in Q1 and Q2. 0 <= N.

           X1

                     X1 is DOUBLE PRECISION array, dimension (M1)
                      On entry, the top part of the vector to be orthogonalized.
                      On exit, the top part of the projected vector.

           INCX1

                     INCX1 is INTEGER
                      Increment for entries of X1.

           X2

                     X2 is DOUBLE PRECISION array, dimension (M2)
                      On entry, the bottom part of the vector to be
                      orthogonalized. On exit, the bottom part of the projected
                      vector.

           INCX2

                     INCX2 is INTEGER
                      Increment for entries of X2.

           Q1

                     Q1 is DOUBLE PRECISION array, dimension (LDQ1, N)
                      The top part of the orthonormal basis matrix.

           LDQ1

                     LDQ1 is INTEGER
                      The leading dimension of Q1. LDQ1 >= M1.

           Q2

                     Q2 is DOUBLE PRECISION array, dimension (LDQ2, N)
                      The bottom part of the orthonormal basis matrix.

           LDQ2

                     LDQ2 is INTEGER
                      The leading dimension of Q2. LDQ2 >= M2.

           WORK

                     WORK is DOUBLE PRECISION array, dimension (LWORK)

           LWORK

                     LWORK is INTEGER
                      The dimension of the array WORK. LWORK >= 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.

   subroutine sorbdb5 (integer m1, integer m2, integer n, real, dimension(*) x1, integer incx1,
       real, dimension(*) x2, integer incx2, real, dimension(ldq1,*) q1, integer ldq1, real,
       dimension(ldq2,*) q2, integer ldq2, real, dimension(*) work, integer lwork, integer info)
       SORBDB5

       Purpose:

            SORBDB5 orthogonalizes the column vector
                 X = [ X1 ]
                     [ X2 ]
            with respect to the columns of
                 Q = [ Q1 ] .
                     [ Q2 ]
            The columns of Q must be orthonormal.

            If the projection is zero according to Kahan's 'twice is enough'
            criterion, then some other vector from the orthogonal complement
            is returned. This vector is chosen in an arbitrary but deterministic
            way.

       Parameters
           M1

                     M1 is INTEGER
                      The dimension of X1 and the number of rows in Q1. 0 <= M1.

           M2

                     M2 is INTEGER
                      The dimension of X2 and the number of rows in Q2. 0 <= M2.

           N

                     N is INTEGER
                      The number of columns in Q1 and Q2. 0 <= N.

           X1

                     X1 is REAL array, dimension (M1)
                      On entry, the top part of the vector to be orthogonalized.
                      On exit, the top part of the projected vector.

           INCX1

                     INCX1 is INTEGER
                      Increment for entries of X1.

           X2

                     X2 is REAL array, dimension (M2)
                      On entry, the bottom part of the vector to be
                      orthogonalized. On exit, the bottom part of the projected
                      vector.

           INCX2

                     INCX2 is INTEGER
                      Increment for entries of X2.

           Q1

                     Q1 is REAL array, dimension (LDQ1, N)
                      The top part of the orthonormal basis matrix.

           LDQ1

                     LDQ1 is INTEGER
                      The leading dimension of Q1. LDQ1 >= M1.

           Q2

                     Q2 is REAL array, dimension (LDQ2, N)
                      The bottom part of the orthonormal basis matrix.

           LDQ2

                     LDQ2 is INTEGER
                      The leading dimension of Q2. LDQ2 >= M2.

           WORK

                     WORK is REAL array, dimension (LWORK)

           LWORK

                     LWORK is INTEGER
                      The dimension of the array WORK. LWORK >= 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.

   subroutine zunbdb5 (integer m1, integer m2, integer n, complex*16, dimension(*) x1, integer
       incx1, complex*16, dimension(*) x2, integer incx2, complex*16, dimension(ldq1,*) q1,
       integer ldq1, complex*16, dimension(ldq2,*) q2, integer ldq2, complex*16, dimension(*)
       work, integer lwork, integer info)
       ZUNBDB5

       Purpose:

            ZUNBDB5 orthogonalizes the column vector
                 X = [ X1 ]
                     [ X2 ]
            with respect to the columns of
                 Q = [ Q1 ] .
                     [ Q2 ]
            The columns of Q must be orthonormal.

            If the projection is zero according to Kahan's 'twice is enough'
            criterion, then some other vector from the orthogonal complement
            is returned. This vector is chosen in an arbitrary but deterministic
            way.

       Parameters
           M1

                     M1 is INTEGER
                      The dimension of X1 and the number of rows in Q1. 0 <= M1.

           M2

                     M2 is INTEGER
                      The dimension of X2 and the number of rows in Q2. 0 <= M2.

           N

                     N is INTEGER
                      The number of columns in Q1 and Q2. 0 <= N.

           X1

                     X1 is COMPLEX*16 array, dimension (M1)
                      On entry, the top part of the vector to be orthogonalized.
                      On exit, the top part of the projected vector.

           INCX1

                     INCX1 is INTEGER
                      Increment for entries of X1.

           X2

                     X2 is COMPLEX*16 array, dimension (M2)
                      On entry, the bottom part of the vector to be
                      orthogonalized. On exit, the bottom part of the projected
                      vector.

           INCX2

                     INCX2 is INTEGER
                      Increment for entries of X2.

           Q1

                     Q1 is COMPLEX*16 array, dimension (LDQ1, N)
                      The top part of the orthonormal basis matrix.

           LDQ1

                     LDQ1 is INTEGER
                      The leading dimension of Q1. LDQ1 >= M1.

           Q2

                     Q2 is COMPLEX*16 array, dimension (LDQ2, N)
                      The bottom part of the orthonormal basis matrix.

           LDQ2

                     LDQ2 is INTEGER
                      The leading dimension of Q2. LDQ2 >= M2.

           WORK

                     WORK is COMPLEX*16 array, dimension (LWORK)

           LWORK

                     LWORK is INTEGER
                      The dimension of the array WORK. LWORK >= 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.

Author

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