SLATEC Routines --- PVALUE ---

*DECK PVALUE
      SUBROUTINE PVALUE (L, NDER, X, YFIT, YP, A)
C***BEGIN PROLOGUE  PVALUE
C***PURPOSE  Use the coefficients generated by POLFIT to evaluate the
C            polynomial fit of degree L, along with the first NDER of
C            its derivatives, at a specified point.
C***LIBRARY   SLATEC
C***CATEGORY  K6
C***TYPE      SINGLE PRECISION (PVALUE-S, DP1VLU-D)
C***KEYWORDS  CURVE FITTING, LEAST SQUARES, POLYNOMIAL APPROXIMATION
C***AUTHOR  Shampine, L. F., (SNLA)
C           Davenport, S. M., (SNLA)
C***DESCRIPTION
C
C     Written by L. F. Shampine and S. M. Davenport.
C
C     Abstract
C
C     The subroutine  PVALUE  uses the coefficients generated by  POLFIT
C     to evaluate the polynomial fit of degree  L , along with the first
C     NDER  of its derivatives, at a specified point.  Computationally
C     stable recurrence relations are used to perform this task.
C
C     The parameters for  PVALUE  are
C
C     Input --
C         L -      the degree of polynomial to be evaluated.  L  may be
C                  any non-negative integer which is less than or equal
C                  to  NDEG , the highest degree polynomial provided
C                  by  POLFIT .
C         NDER -   the number of derivatives to be evaluated.  NDER
C                  may be 0 or any positive value.  If NDER is less
C                  than 0, it will be treated as 0.
C         X -      the argument at which the polynomial and its
C                  derivatives are to be evaluated.
C         A -      work and output array containing values from last
C                  call to  POLFIT .
C
C     Output --
C         YFIT -   value of the fitting polynomial of degree  L  at  X
C         YP -     array containing the first through  NDER  derivatives
C                  of the polynomial of degree  L .  YP  must be
C                  dimensioned at least  NDER  in the calling program.
C
C***REFERENCES  L. F. Shampine, S. M. Davenport and R. E. Huddleston,
C                 Curve fitting by polynomials in one variable, Report
C                 SLA-74-0270, Sandia Laboratories, June 1974.
C***ROUTINES CALLED  XERMSG
C***REVISION HISTORY  (YYMMDD)
C   740601  DATE WRITTEN
C   890531  Changed all specific intrinsics to generic.  (WRB)
C   890531  REVISION DATE from Version 3.2
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ)
C   900510  Convert XERRWV calls to XERMSG calls.  (RWC)
C   920501  Reformatted the REFERENCES section.  (WRB)
C***END PROLOGUE  PVALUE