sintrp.f
SUBROUTINE SINTRP (X, Y, XOUT, YOUT, YPOUT, NEQN, KOLD, PHI, IVC,
+ IV, KGI, GI, ALPHA, OG, OW, OX, OY)
C***BEGIN PROLOGUE SINTRP
C***PURPOSE Approximate the solution at XOUT by evaluating the
C polynomial computed in STEPS at XOUT. Must be used in
C conjunction with STEPS.
C***LIBRARY SLATEC (DEPAC)
C***CATEGORY I1A1B
C***TYPE SINGLE PRECISION (SINTRP-S, DINTP-D)
C***KEYWORDS ADAMS METHOD, DEPAC, INITIAL VALUE PROBLEMS, ODE,
C ORDINARY DIFFERENTIAL EQUATIONS, PREDICTOR-CORRECTOR,
C SMOOTH INTERPOLANT
C***AUTHOR Watts, H. A., (SNLA)
C***DESCRIPTION
C
C The methods in subroutine STEPS approximate the solution near X
C by a polynomial. Subroutine SINTRP approximates the solution at
C XOUT by evaluating the polynomial there. Information defining this
C polynomial is passed from STEPS so SINTRP cannot be used alone.
C
C Subroutine STEPS is completely explained and documented in the text,
C "Computer Solution of Ordinary Differential Equations, the Initial
C Value Problem" by L. F. Shampine and M. K. Gordon.
C
C Input to SINTRP --
C
C The user provides storage in the calling program for the arrays in
C the call list
C DIMENSION Y(NEQN),YOUT(NEQN),YPOUT(NEQN),PHI(NEQN,16),OY(NEQN)
C AND ALPHA(12),OG(13),OW(12),GI(11),IV(10)
C and defines
C XOUT -- point at which solution is desired.
C The remaining parameters are defined in STEPS and passed to
C SINTRP from that subroutine
C
C Output from SINTRP --
C
C YOUT(*) -- solution at XOUT
C YPOUT(*) -- derivative of solution at XOUT
C The remaining parameters are returned unaltered from their input
C values. Integration with STEPS may be continued.
C
C***REFERENCES H. A. Watts, A smoother interpolant for DE/STEP, INTRP
C II, Report SAND84-0293, Sandia Laboratories, 1984.
C***ROUTINES CALLED (NONE)
C***REVISION HISTORY (YYMMDD)
C 840201 DATE WRITTEN
C 890831 Modified array declarations. (WRB)
C 890831 REVISION DATE from Version 3.2
C 891214 Prologue converted to Version 4.0 format. (BAB)
C 920501 Reformatted the REFERENCES section. (WRB)
C***END PROLOGUE SINTRP