TESTING/EIG/sget51.f(3)    Library Functions Manual    TESTING/EIG/sget51.f(3)

NAME
       TESTING/EIG/sget51.f

SYNOPSIS
   Functions/Subroutines
       subroutine sget51 (itype, n, a, lda, b, ldb, u, ldu, v, ldv, work,
           result)
           SGET51

Function/Subroutine Documentation
   subroutine sget51 (integer itype, integer n, real, dimension( lda, * ) a,
       integer lda, real, dimension( ldb, * ) b, integer ldb, real, dimension(
       ldu, * ) u, integer ldu, real, dimension( ldv, * ) v, integer ldv,
       real, dimension( * ) work, real result)
       SGET51

       Purpose:


                 SGET51  generally checks a decomposition of the form

                         A = U B V'

                 where ' means transpose and U and V are orthogonal.

                 Specifically, if ITYPE=1

                         RESULT = | A - U B V' | / ( |A| n ulp )

                 If ITYPE=2, then:

                         RESULT = | A - B | / ( |A| n ulp )

                 If ITYPE=3, then:

                         RESULT = | I - UU' | / ( n ulp )

       Parameters
           ITYPE

                     ITYPE is INTEGER
                     Specifies the type of tests to be performed.
                     =1: RESULT = | A - U B V' | / ( |A| n ulp )
                     =2: RESULT = | A - B | / ( |A| n ulp )
                     =3: RESULT = | I - UU' | / ( n ulp )

           N

                     N is INTEGER
                     The size of the matrix.  If it is zero, SGET51 does nothing.
                     It must be at least zero.

           A

                     A is REAL array, dimension (LDA, N)
                     The original (unfactored) matrix.

           LDA

                     LDA is INTEGER
                     The leading dimension of A.  It must be at least 1
                     and at least N.

           B

                     B is REAL array, dimension (LDB, N)
                     The factored matrix.

           LDB

                     LDB is INTEGER
                     The leading dimension of B.  It must be at least 1
                     and at least N.

           U

                     U is REAL array, dimension (LDU, N)
                     The orthogonal matrix on the left-hand side in the
                     decomposition.
                     Not referenced if ITYPE=2

           LDU

                     LDU is INTEGER
                     The leading dimension of U.  LDU must be at least N and
                     at least 1.

           V

                     V is REAL array, dimension (LDV, N)
                     The orthogonal matrix on the left-hand side in the
                     decomposition.
                     Not referenced if ITYPE=2

           LDV

                     LDV is INTEGER
                     The leading dimension of V.  LDV must be at least N and
                     at least 1.

           WORK

                     WORK is REAL array, dimension (2*N**2)

           RESULT

                     RESULT is REAL
                     The values computed by the test specified by ITYPE.  The
                     value is currently limited to 1/ulp, to avoid overflow.
                     Errors are flagged by RESULT=10/ulp.

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 147 of file sget51.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0         TESTING/EIG/sget51.f(3)