Subroutine Type

Modeling

Definition

Calculates an algebraic value for a user defined variable element.

Use

User-defined variable calling a VARSUB for the calculation of its algebraic values:

<Reference_Variable

    id                  = "30100100"

    type                = "USERSUB"

    usrsub_param_string = "USER(30131,30100,0.01,1)"

    usrsub_dll_name     = "NULL"

/>

Calling Syntax

Fortran

SUBROUTINE VARSUB(ID, TIME, PAR, NPAR, DFLAG, IFLAG, VALUE)

C

void STDCALL VARSUB (int *id, double *time, double *par, int *npar, int *dflag, int *iflag, double *value)

Python

def VARSUB(id, time, par, npar, dflag, iflag):

    return value

MATLAB

function value = VARSUB(id, time, par, npar, dflag, iflag)

Input Arguments

[integer] ID

The user-defined variable element identifier.

[double precision] TIME

The current simulation time.

[double precision] PAR

An array that contains the constant arguments from the list provided in the user defined statement.

[integer] NPAR

The number of entries in the PAR array.

[logical] DFLAG

The differentiating flag.

[logical] IFLAG

The initialization flag.

Output Values

[double precision] VALUE

The output that contains the algebraic variable value that the VARSUB has computed.

Example

def VARSUB(id, time, par, npar, dflag, iflag):

    ipar = 2*[0]

    ipar[0] = int(par[0])

    ipar[1] = int(par[1])

    [dz, errflg] = py_sysfnc("DZ", ipar)

    py_errmes(errflg, "Error calling SYSFNC for DZ", id, "STOP")

    [vz, errflg] = py_sysfnc("VZ", ipar)

    py_errmes(errflg, "Error calling SYSFNC for VZ", id, "STOP")

    value = -par[2]*vz - par[3]*dz

    return value