DINTP(3)

SYNOPSIS
SUBROUTINE DINTP (X, Y, XOUT, YOUT, YPOUT, NEQN, KOLD, PHI, IVC, + IV, KGI, GI, ALPHA, OG, OW, OX, OY)

NAME
dintp - Approximate the solution at XOUT by evaluating the polynomial computed in DSTEPS at XOUT. Must be used in conjunction with DSTEPS.

LIBRARY
SLATEC (DEPAC)

CATEGORY
I1A1B

TYPE
DOUBLE PRECISION (SINTRP-S, DINTP-D)

KEYWORDS
ADAMS METHOD, DEPAC, INITIAL VALUE PROBLEMS, ODE, ORDINARY DIFFERENTIAL EQUATIONS, PREDICTOR-CORRECTOR, SMOOTH INTERPOLANT

AUTHOR
Watts, H. A., (SNLA)

DESCRIPTION
The methods in subroutine DSTEPS approximate the solution near X by a polynomial. Subroutine DINTP approximates the solution at XOUT by evaluating the polynomial there. Information defining this polynomial is passed from DSTEPS so DINTP cannot be used alone. Subroutine DSTEPS is completely explained and documented in the text "Computer Solution of Ordinary Differential Equations, the Initial Value Problem" by L. F. Shampine and M. K. Gordon. Input to DINTP -- The user provides storage in the calling program for the arrays in the call list DIMENSION Y(NEQN),YOUT(NEQN),YPOUT(NEQN),PHI(NEQN,16),OY(NEQN) AND ALPHA(12),OG(13),OW(12),GI(11),IV(10) and defines XOUT -- point at which solution is desired. The remaining parameters are defined in DSTEPS and passed to DINTP from that subroutine Output from DINTP -- YOUT(*) -- solution at XOUT YPOUT(*) -- derivative of solution at XOUT The remaining parameters are returned unaltered from their input values. Integration with DSTEPS may be continued.

REFERENCES
H. A. Watts, A smoother interpolant for DE/STEP, INTRP II, Report SAND84-0293, Sandia Laboratories, 1984.

ROUTINES CALLED
(NONE)

REVISION HISTORY (YYMMDD)
840201 DATE WRITTEN
890831 Modified array declarations. (WRB)
890831 REVISION DATE from Version 3.2
891214 Prologue converted to Version 4.0 format. (BAB)
920501 Reformatted the REFERENCES section. (WRB)