The routine and its subsidiaries will now
return an error status as supplied by PDA_XERMSG.
SUBROUTINE PDA_DP1VLU (L, NDER, X, YFIT, YP, A, STATUS)
***BEGIN PROLOGUE PDA_DP1VLU
***PURPOSE Use the coefficients generated by PDA_DPOLFT to evaluate the
polynomial fit of degree L, along with the first NDER of
its derivatives, at a specified point.
***TYPE DOUBLE PRECISION (PVALUE-S, PDA_DP1VLU-D)
***KEYWORDS CURVE FITTING, LEAST SQUARES, POLYNOMIAL APPROXIMATION
***AUTHOR Shampine, L. F., (SNLA)
Davenport, S. M., (SNLA)
The subroutine PDA_DP1VLU uses the coefficients generated by PDA_DPOLFT
to evaluate the polynomial fit of degree L , along with the first
NDER of its derivatives, at a specified point. Computationally
stable recurrence relations are used to perform this task.
The parameters for PDA_DP1VLU are
Input -- ALL TYPE REAL variables are DOUBLE PRECISION
L - the degree of polynomial to be evaluated. L may be
any non-negative integer which is less than or equal
to NDEG , the highest degree polynomial provided
by PDA_DPOLFT .
NDER - the number of derivatives to be evaluated. NDER
may be 0 or any positive value. If NDER is less
than 0, it will be treated as 0.
X - the argument at which the polynomial and its
derivatives are to be evaluated.
A - work and output array containing values from last
call to PDA_DPOLFT .
Output -- ALL TYPE REAL variables are DOUBLE PRECISION
YFIT - value of the fitting polynomial of degree L at X
YP - array containing the first through NDER derivatives
of the polynomial of degree L . YP must be
dimensioned at least NDER in the calling program.
STATUS - Returned error status.
The status must be zero on entry. This
routine does not check the status on entry.
***REFERENCES L. F. Shampine, S. M. Davenport and R. E. Huddleston,
Curve fitting by polynomials in one variable, Report
SLA-74-0270, Sandia Laboratories, June 1974.
***ROUTINES CALLED PDA_XERMSG
***REVISION HISTORY (YYMMDD)
740601 DATE WRITTEN
890531 Changed all specific intrinsics to generic. (WRB)
890911 Removed unnecessary intrinsics. (WRB)
891006 Cosmetic changes to prologue. (WRB)
891006 REVISION DATE from Version 3.2
891214 Prologue converted to Version 4.0 format. (BAB)
900315 CALLs to XERROR changed to CALLs to PDA_XERMSG. (THJ)
900510 Convert XERRWV calls to PDA_XERMSG calls. (RWC)
920501 Reformatted the REFERENCES section. (WRB)
950404 Implement status. (HME)
***END PROLOGUE PDA_DP1VLU