Welcome to Adams/Solver Subroutines - Kxcad.net

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Adams/Solver
Input Arguments
id An integer variable that contains the ID of the SFORCE statement that
requests information from SFOSUB. From the identifier, Adams/Solver
automatically knows other information (such as the par argument)
available in the corresponding statement.
time A double-precision variable through which Adams/Solver conveys the
current simulation time.
par A double-precision array of constants taken in order from the USER
parenthetical list of the SFORCE statement.
dflag A logical variable that Adams/Solver sets to true when it calls SFOSUB
to evaluate partial derivatives of the function. Otherwise, Adams/Solver
sets dflag to false. See Using the DFLAG Variable.
npar An integer variable that indicates the number of constants specified in the
USER parenthetical list. The primary purpose of npar is to provide
SFOSUB with the number of values stored in the par array.
iflag A logical variable that Adams/Solver sets to true when it needs the
functional dependency of the user-defined SFORCE. Set functional
dependencies by making the same calls to SYSARY and SYSFNC that
you make to compute the value of the user-defined SFORCE (see
SYSARY and SYSFNC). If the iflag argument is false, compute the value
of the user-written SFORCE.
Output Argument
value A double-precision variable that contains the force value that SFOSUB
computes.
Extended Definition
The SFORCE statement (C++ or FORTRAN) with a function expression is usually adequate for defining
most single-component forces. If the expression becomes lengthy and awkward, however, you should use
the FUNCTION=USER() argument in the SFORCE statement, and write an SFOSUB to calculate the
single-component force.
You can call utility subroutines, such as SYSARY, SYSFNC, AKISPL, and CUBSPL, from SFOSUB to
obtain information about system variables, user-defined variables, and splines.
The SYSARY and SYSFNC utility subroutines automatically set functional dependencies when the
SFOSUB argument iflag is true. For Adams/Solver to compute solutions efficiently, it must know
on which other variables each user-defined SFORCE directly depends. Adams/Solver determines these
functional dependencies at the beginning of the simulation by calling SFOSUB evaluation subroutine
with argument iflag set to true. Adams/Solver does this once for each SFORCE statement with a
FUNCTION=USER() argument. During each call to SFOSUB, Adams/Solver records which calls you