PDA_DPOLCF - Coefficients of the polynomial fit (including Hermite polynomial fits) produced by PDA_DPLINT.

Origin

SLATEC / CAMSUN

      SUBROUTINE PDA_DPOLCF (XX, N, X, C, D, WORK)


***BEGIN PROLOGUE  PDA_DPOLCF
***PURPOSE  Compute the coefficients of the polynomial fit (including
            Hermite polynomial fits) produced by a previous call to
            POLINT.
***LIBRARY   SLATEC
***CATEGORY  E1B
***TYPE      DOUBLE PRECISION (POLCOF-S, PDA_DPOLCF-D)
***KEYWORDS  COEFFICIENTS, POLYNOMIAL
***AUTHOR  Huddleston, R. E., (SNLL)
***DESCRIPTION

     Abstract
        Subroutine PDA_DPOLCF computes the coefficients of the polynomial
     fit (including Hermite polynomial fits ) produced by a previous
     call to PDA_DPLINT.  The coefficients of the polynomial, expanded
     about XX, are stored in the array D. The expansion is of the form
     P(Z) = D(1) + D(2)*(Z-XX) +D(3)*((Z-XX)**2) + ... +
                                                  D(N)*((Z-XX)**(N-1)).
     Between the call to PDA_DPLINT and the call to PDA_DPOLCF the variable N
     and the arrays X and C must not be altered.

     *****  INPUT PARAMETERS
      *** All TYPE REAL variables are DOUBLE PRECISION ***

     XX   - The point about which the Taylor expansion is to be made.

     N    - ****
            *     N, X, and C must remain unchanged between the
     X    - *     call to PDA_DPLINT and the call to PDA_DPOLCF.
     C    - ****

     *****  OUTPUT PARAMETER
      *** All TYPE REAL variables are DOUBLE PRECISION ***

     D    - The array of coefficients for the Taylor expansion as
            explained in the abstract

     *****  STORAGE PARAMETER

     WORK - This is an array to provide internal working storage. It
            must be dimensioned by at least 2*N in the calling program.


     **** Note - There are two methods for evaluating the fit produced
     by PDA_DPLINT. You may call PDA_DPOLVL to perform the task, or you may
     call PDA_DPOLCF to obtain the coefficients of the Taylor expansion and
     then write your own evaluation scheme. Due to the inherent errors
     in the computations of the Taylor expansion from the Newton
     coefficients produced by PDA_DPLINT, much more accuracy may be
     expected by calling PDA_DPOLVL as opposed to writing your own scheme.

***REFERENCES  (NONE)
***ROUTINES CALLED  (NONE)
***REVISION HISTORY  (YYMMDD)
   890213  DATE WRITTEN
   891006  Cosmetic changes to prologue.  (WRB)
   891024  Corrected KEYWORD section.  (WRB)
   891024  REVISION DATE from Version 3.2
   891214  Prologue converted to Version 4.0 format.  (BAB)
***END PROLOGUE  PDA_DPOLCF