Welcome to Adams/Solver Subroutines - Kxcad.net

102
Adams/Solver
argument is false, SYSARY returns the instantaneous values of the system states. You can make several
calls to SYSARY, specifying each time the function used, and the parameters of the function.
Tip: 1. Use SYSFNC to access individual states. Quite often, user-defined values depend
on a single-system state such as the x component of the displacement between two
markers, or the z component of the velocity between two markers. While you can
use SYSARY to access the individual components, a single call to SYSFNC is
convenient and more efficient. The use of SYSFNC is therefore recommended
under these circumstances.
Examples
2. Use RCNVRT to convert rotational displacements Euler angles to any other angle
representation, for example Adams AX, AY, AZ projected angles.
CALL SYSFNC (`RDISP', IPAR, 2, ANGLES, NSTATE, ERRFLG)
CALL RCNVRT (`EULER', ANGLES, `AXAYAZ', ANGLES, ISTAT)
Use SYSFNC to access individual states.Quite often, user-defined values depend
on a single-system state such as the x component of the displacement between two
markers. While you may use SYSARY to access the individual components, a
single call to SYSFNC is convenient and more efficient. The use of SYSFNC is
therefore recommended under these circumstances.
Caution: When the iflag argument is true, you must be sure to make the same SYSARY calls as when
actually computing the results. Adams/Solver passes a parameter iflag to each user-written
subroutine (xxxSUB). It indicates to you whether Adams/Solver is calling the subroutine
for an initialization pass (iflag = true) or for a function evaluation (iflag =false). You must
construct user-written subroutines such that all calls to SYSARY that are made during the
simulation are also invoked when the iflag argument is true. Adams/Solver uses this
information to construct the correct Jacobian matrix.
This example shows properly written calls to SYSARY for UVX, UVY, UVE, and DC.
SUBROUTINE VARSUB (ID, TIME, PAR, NPAR, DFLAG, IFLAG, VALUE)
C
C Inputs:
C
INTEGER ID, NPAR
DOUBLE PRECISION TIME, PAR(*)
LOGICAL DFLAG, IFLAG
C
C Outputs:
C
LOGICAL VALUE
C
C Local Variables: