BD02AD

Benchmark examples for time-invariant discrete-time dynamical systems

[Specification] [Arguments] [Method] [References] [Comments] [Example]

Purpose

  To generate benchmark examples for time-invariant,
  discrete-time dynamical systems

    E x_k+1 = A x_k + B u_k

        y_k = C x_k + D u_k

  E, A are real N-by-N matrices, B is N-by-M, C is P-by-N, and
  D is P-by-M. In many examples, E is the identity matrix and D is
  the zero matrix.

  This routine is an implementation of the benchmark library
  DTDSX (Version 1.0) described in [1].

Specification
      SUBROUTINE BD02AD( DEF, NR, DPAR, IPAR, VEC, N, M, P, E, LDE, A,
     1                   LDA, B, LDB, C, LDC, D, LDD, NOTE, DWORK,
     2                   LDWORK, INFO )
C     .. Scalar Arguments ..
      CHARACTER         DEF
      CHARACTER*70      NOTE
      INTEGER           INFO, LDA, LDB, LDC, LDD, LDE, LDWORK, M, N, P
C     .. Array Arguments ..
      LOGICAL           VEC(8)
      INTEGER           IPAR(*), NR(*)
      DOUBLE PRECISION  A(LDA,*), B(LDB,*), C(LDC,*), D(LDD,*), DPAR(*),
     1                  DWORK(*), E(LDE,*)

Arguments

Mode Parameters

  DEF     CHARACTER*1
          Specifies the kind of values used as parameters when
          generating parameter-dependent and scalable examples
          (i.e., examples with NR(1) = 2, 3, or 4):
          = 'D':  Default values defined in [1] are used;
          = 'N':  Values set in DPAR and IPAR are used.
          This parameter is not referenced if NR(1) = 1.
          Note that the scaling parameter of examples with
          NR(1) = 3 or 4 is considered as a regular parameter in
          this context.

Input/Output Parameters
  NR      (input) INTEGER array, dimension (2)
          Specifies the index of the desired example according
          to [1].
          NR(1) defines the group:
                1 : parameter-free problems of fixed size
                2 : parameter-dependent problems of fixed size
                3 : parameter-free problems of scalable size
                4 : parameter-dependent problems of scalable size
          NR(2) defines the number of the benchmark example
          within a certain group according to [1].

  DPAR    (input/output) DOUBLE PRECISION array, dimension (7)
          On entry, if DEF = 'N' and the desired example depends on
          real parameters, then the array DPAR must contain the
          values for these parameters.
          For an explanation of the parameters see [1].
          For Example 2.1, DPAR(1), ..., DPAR(3) define the
          parameters 'tau', 'delta', 'K', respectively.
          On exit, if DEF = 'D' and the desired example depends on
          real parameters, then the array DPAR is overwritten by the
          default values given in [1].

  IPAR    (input/output) INTEGER array, dimension (1)
          On entry, if DEF = 'N' and the desired example depends on
          integer parameters, then the array IPAR must contain the
          values for these parameters.
          For an explanation of the parameters see [1].
          For Example 3.1, IPAR(1) defines the parameter 'n'.
          On exit, if DEF = 'D' and the desired example depends on
          integer parameters, then the array IPAR is overwritten by
          the default values given in [1].

  VEC     (output) LOGICAL array, dimension (8)
          Flag vector which displays the availabilty of the output
          data:
          VEC(1), ..., VEC(3) refer to N, M, and P, respectively,
          and are always .TRUE..
          VEC(4) is .TRUE. iff E is NOT the identity matrix.
          VEC(5), ..., VEC(7) refer to A, B, and C, respectively,
          and are always .TRUE..
          VEC(8) is .TRUE. iff D is NOT the zero matrix.

  N       (output) INTEGER
          The actual state dimension, i.e., the order of the
          matrices E and A.

  M       (output) INTEGER
          The number of columns in the matrices B and D.

  P       (output) INTEGER
          The number of rows in the matrices C and D.

  E       (output) DOUBLE PRECISION array, dimension (LDE,N)
          The leading N-by-N part of this array contains the
          matrix E.
          NOTE that this array is overwritten (by the identity
          matrix), if VEC(4) = .FALSE..

  LDE     INTEGER
          The leading dimension of array E.  LDE >= N.

  A       (output) DOUBLE PRECISION array, dimension (LDA,N)
          The leading N-by-N part of this array contains the
          matrix A.

  LDA     INTEGER
          The leading dimension of array A.  LDA >= N.

  B       (output) DOUBLE PRECISION array, dimension (LDB,M)
          The leading N-by-M part of this array contains the
          matrix B.

  LDB     INTEGER
          The leading dimension of array B.  LDB >= N.

  C       (output) DOUBLE PRECISION array, dimension (LDC,N)
          The leading P-by-N part of this array contains the
          matrix C.

  LDC     INTEGER
          The leading dimension of array C.  LDC >= P.

  D       (output) DOUBLE PRECISION array, dimension (LDD,M)
          The leading P-by-M part of this array contains the
          matrix D.
          NOTE that this array is overwritten (by the zero
          matrix), if VEC(8) = .FALSE..

  LDD     INTEGER
          The leading dimension of array D.  LDD >= P.

  NOTE    (output) CHARACTER*70
          String containing short information about the chosen
          example.

Workspace
  DWORK   DOUBLE PRECISION array, dimension (LDWORK)
          NOTE that DWORK is not used in the current version
          of BD02AD.

  LDWORK  INTEGER
          LDWORK >= 1.

Error Indicator
  INFO    INTEGER
          = 0:  successful exit;
          < 0:  if INFO = -i, the i-th argument had an illegal
                value; in particular, INFO = -3 or -4 indicates
                that at least one of the parameters in DPAR or
                IPAR, respectively, has an illegal value;
          = 1:  data file can not be opened or has wrong format.

References
  [1]  Kressner, D., Mehrmann, V. and Penzl, T.
       DTDSX - a Collection of Benchmark Examples for State-Space
       Realizations of Discrete-Time Dynamical Systems.
       SLICOT Working Note 1998-10. 1998.

Numerical Aspects
  None

Further Comments
  None
Example

Program Text

C     BD02AD EXAMPLE PROGRAM TEXT
C     Copyright (c) 2002-2017 NICONET e.V.
C
C     .. Parameters ..
      INTEGER          NIN, NOUT
      PARAMETER        (NIN = 5, NOUT = 6)
      INTEGER          NMAX, MMAX, PMAX
      PARAMETER        (NMAX = 421, MMAX = 211, PMAX = 211)
      INTEGER          LDA, LDB, LDC, LDD, LDE, LDWORK
      PARAMETER        (LDA = NMAX, LDB = NMAX, LDC = PMAX, LDD = PMAX,
     1                  LDE = NMAX, LDWORK = 1)
C     .. Local Scalars ..
      CHARACTER        DEF
      INTEGER          I, INFO, J, LDPAR, LIPAR, M, N, P
      CHARACTER*70     NOTE
C     .. Local Arrays ..
      DOUBLE PRECISION A(LDA,NMAX), B(LDB,MMAX), C(LDC,NMAX),
     1                 D(LDD,MMAX), DPAR(7), DWORK(LDWORK), E(LDE,NMAX)
      INTEGER          NR(2), IPAR(7)
      LOGICAL          VEC(8)
C     .. External Functions ..
      LOGICAL          LSAME
      EXTERNAL         LSAME
C     .. External Subroutines ..
      EXTERNAL         BD02AD
C     .. Executable Statements ..
      WRITE (NOUT, FMT = 99999)
C     Skip the heading in the data file and read the data.
      READ (NIN, FMT = '()')
      READ (NIN, FMT = *) DEF
      READ (NIN, FMT = *) (NR(I), I = 1, 2)
      IF (LSAME(DEF,'N')) THEN
        READ (NIN, FMT = *) LDPAR
        IF (LDPAR .GT. 0)  READ (NIN, FMT = *) (DPAR(I), I = 1, LDPAR)
        READ (NIN, FMT = *) LIPAR
        IF (LIPAR .GT. 0)  READ (NIN, FMT = *) (IPAR(I), I = 1, LIPAR)
      END IF
C     Generate benchmark example
      CALL BD02AD(DEF, NR, DPAR, IPAR, VEC, N, M, P, E, LDE, A, LDA,
     1            B, LDB, C, LDC, D, LDD, NOTE, DWORK, LDWORK, INFO)
C
      IF (INFO .NE. 0) THEN
        WRITE (NOUT, FMT = 99998) INFO
      ELSE
        WRITE (NOUT, FMT = *) NOTE
        WRITE (NOUT, FMT = 99997) N
        WRITE (NOUT, FMT = 99996) M
        WRITE (NOUT, FMT = 99995) P
        IF (VEC(4)) THEN
          WRITE (NOUT, FMT = 99994)
          DO 10  I = 1, N
            WRITE (NOUT, FMT = 99987) (E(I,J), J = 1, N)
10        CONTINUE
        ELSE
          WRITE (NOUT, FMT = 99993)
        END IF
        WRITE (NOUT,FMT = 99992)
        DO 20  I = 1, N
          WRITE (NOUT, FMT = 99987) (A(I,J), J = 1, N)
20      CONTINUE
        WRITE (NOUT,FMT = 99991)
        DO 30  I = 1, N
          WRITE (NOUT, FMT = 99987) (B(I,J), J = 1, M)
30      CONTINUE
        WRITE (NOUT,FMT = 99990)
        DO 40  I = 1, P
          WRITE (NOUT, FMT = 99987) (C(I,J), J = 1, N)
40      CONTINUE
        IF (VEC(8)) THEN
          WRITE (NOUT,FMT = 99989)
          DO 50  I = 1, P
            WRITE (NOUT, FMT = 99987) (D(I,J), J = 1, M)
50        CONTINUE
        ELSE
          WRITE (NOUT, FMT = 99988)
        END IF
      END IF
C
99999 FORMAT (' BD02AD EXAMPLE PROGRAM RESULTS', /1X)
99998 FORMAT (' INFO on exit from BD02AD = ', I3)
99997 FORMAT (/' Order of matrix A:               N  = ', I3)
99996 FORMAT (' Number of columns in matrix B:   M  = ', I3)
99995 FORMAT (' Number of rows in matrix C:      P  = ', I3)
99994 FORMAT (/' E  = ')
99993 FORMAT (/' E is the identity matrix.')
99992 FORMAT (' A  = ')
99991 FORMAT (' B  = ')
99990 FORMAT (' C  = ')
99989 FORMAT (' D  = ')
99988 FORMAT (' D is of zeros.')
99987 FORMAT (20(1X,F8.4))
C
      END
Program Data
BD02AD EXAMPLE PROGRAM DATA
D
1 1
Program Results
 BD02AD EXAMPLE PROGRAM RESULTS

 Laub 1979, Ex. 2: uncontrollable-unobservable data                    

 Order of matrix A:               N  =   2
 Number of columns in matrix B:   M  =   1
 Number of rows in matrix C:      P  =   1

 E is the identity matrix.
 A  = 
   4.0000   3.0000
  -4.5000  -3.5000
 B  = 
   1.0000
  -1.0000
 C  = 
   3.0000   2.0000
 D is of zeros.

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