UD01BD

Reading a matrix polynomial

Purpose

  To read the coefficients of a matrix polynomial
                                                 dp-1           dp
     P(s) = P(0) + P(1) * s + . . . + P(dp-1) * s    + P(dp) * s  .

      SUBROUTINE UD01BD( MP, NP, DP, NIN, P, LDP1, LDP2, INFO )
C     .. Scalar Arguments ..
      INTEGER           DP, INFO, LDP1, LDP2, MP, NP, NIN
C     .. Array Arguments ..
      DOUBLE PRECISION  P(LDP1,LDP2,*)

Input/Output Parameters

  MP      (input) INTEGER
          The number of rows of the matrix polynomial P(s).
          MP >= 1.

  NP      (input) INTEGER
          The number of columns of the matrix polynomial P(s).
          NP >= 1.

  DP      (input) INTEGER
          The degree of the matrix polynomial P(s).  DP >= 0.

  NIN     (input) INTEGER
          The input channel from which the elements of P(s) are
          read.  NIN >= 0.

  P       (output) DOUBLE PRECISION array, dimension
          (LDP1,LDP2,DP+1)
          The leading MP-by-NP-by-(DP+1) part of this array contains
          the coefficients of the matrix polynomial P(s).
          Specifically, P(i,j,k) contains the coefficient of
          s**(k-1) of the polynomial which is the (i,j)-th element
          of P(s), where i = 1,2,...,MP, j = 1,2,...,NP and
          k = 1,2,...,DP+1.

  LDP1    INTEGER
          The leading dimension of array P.  LDP1 >= MP.

  LDP2    INTEGER
          The second dimension of array P.  LDP2 >= NP.

  INFO    INTEGER
          = 0:  successful exit;
          < 0:  if INFO = -i, the i-th argument had an illegal
                value.

  The coefficients P(i), i = 0, ..., DP, which are MP-by-NP
  matrices, are read from the input file NIN row by row. Each P(i)
  must be preceded by a text line. This text line can be used to
  indicate the coefficient matrices.

  None.

  None.

  None

Program Text

*     UD01BD EXAMPLE PROGRAM TEXT
*     Copyright (c) 2002-2017 NICONET e.V.
*
*     .. Parameters ..
      INTEGER          NIN, NOUT
      PARAMETER        ( NIN = 5, NOUT = 6 )
      INTEGER          MPMAX, NPMAX, DPMAX
      PARAMETER        ( MPMAX = 10, NPMAX = 10, DPMAX = 5 )
      INTEGER          LDP1, LDP2
      PARAMETER        ( LDP1 = MPMAX, LDP2 = NPMAX )
*     .. Local Scalars ..
      INTEGER          DP, INFO, L, MP, NP
*     .. Local Arrays ..
      DOUBLE PRECISION P(LDP1,LDP2,DPMAX)
*     .. External Subroutines ..
      EXTERNAL         UD01BD, UD01ND
*     .. Executable Statements ..
*
      WRITE ( NOUT, FMT = 99999 )
*     Skip the heading in the data file and read the data.
      READ ( NIN, FMT = '()' )
      READ ( NIN, FMT = * ) MP, NP, DP
      IF ( MP.LE.0 .OR. MP.GT.MPMAX ) THEN
         WRITE ( NOUT, FMT = 99994 ) MP
      ELSE IF ( NP.LE.0 .OR. NP.GT.NPMAX ) THEN
         WRITE ( NOUT, FMT = 99995 ) NP
      ELSE IF ( DP.LT.0 .OR. DP.GT.DPMAX ) THEN
         WRITE ( NOUT, FMT = 99993 ) DP
      ELSE
*        Read the coefficients of the matrix polynomial P(s).
         CALL UD01BD( MP, NP, DP, NIN, P, LDP1, LDP2, INFO )
         IF ( INFO.EQ.0 ) THEN
            WRITE ( NOUT, 99996 ) MP, NP, DP
*           Write the coefficients of the matrix polynomial P(s).
            L = 5
            CALL UD01ND( MP, NP, DP, L, NOUT, P, LDP1, LDP2, ' P',
     $                   INFO )
            IF ( INFO.NE.0 )
     $         WRITE ( NOUT, FMT = 99997 ) INFO
         ELSE
            WRITE ( NOUT, FMT = 99998 ) INFO
         END IF
      END IF
      STOP
*
99999 FORMAT (' UD01BD EXAMPLE PROGRAM RESULTS', /1X)
99998 FORMAT (' INFO on exit from UD01BD = ',I2)
99997 FORMAT (' INFO on exit from UD01ND = ',I2)
99996 FORMAT (' MP =', I2, 2X, ' NP =', I2, 3X, 'DP =', I2)
99995 FORMAT (/' NP is out of range.',/' NP = ',I5)
99994 FORMAT (/' MP is out of range.',/' MP = ',I5)
99993 FORMAT (/' DP is out of range.',/' DP = ',I5)
      END

UD01BD EXAMPLE PROGRAM DATA
   4   3   2 
P0
 1.0D-00  0.0D-00  0.0D-00
 0.0D-00  2.0D-00  4.0D-00
 0.0D-00  4.0D-00  8.0D-00
 0.0D-00  6.0D-00  1.2D+01
P1
 0.0D-00  1.0D-00  2.0D-00
 1.0D-00  0.0D-00  0.0D-00
 2.0D-00  0.0D-00  0.0D-00
 3.0D-00  0.0D-00  0.0D-00
P2
 1.0D-00  0.0D-00  0.0D-00
 0.0D-00  0.0D-00  0.0D-00
 0.0D-00  0.0D-00  0.0D-00
 0.0D-00  0.0D-00  0.0D-00

 UD01BD EXAMPLE PROGRAM RESULTS

 MP = 4   NP = 3   DP = 2

  P( 0) ( 4X 3)
            1              2              3
  1    0.1000000D+01  0.0000000D+00  0.0000000D+00
  2    0.0000000D+00  0.2000000D+01  0.4000000D+01
  3    0.0000000D+00  0.4000000D+01  0.8000000D+01
  4    0.0000000D+00  0.6000000D+01  0.1200000D+02

  P( 1) ( 4X 3)
            1              2              3
  1    0.0000000D+00  0.1000000D+01  0.2000000D+01
  2    0.1000000D+01  0.0000000D+00  0.0000000D+00
  3    0.2000000D+01  0.0000000D+00  0.0000000D+00
  4    0.3000000D+01  0.0000000D+00  0.0000000D+00

  P( 2) ( 4X 3)
            1              2              3
  1    0.1000000D+01  0.0000000D+00  0.0000000D+00
  2    0.0000000D+00  0.0000000D+00  0.0000000D+00
  3    0.0000000D+00  0.0000000D+00  0.0000000D+00
  4    0.0000000D+00  0.0000000D+00  0.0000000D+00
 

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