User`s guide

Examples of C MEX-File S-Function Blocks
3-87
"the numerator, nonempty and with first "
"element nonzero");
return;
}
/* xxx verify finite */
if (mxGetNumberOfElements(TS(S)) != 1 || mxGetPr(TS(S))[0] <= 0.0) {
ssSetErrorStatus(S,"Invalid sample time specified");
return;
}
}
#endif /* MDL_CHECK_PARAMETERS */
/* Function: mdlInitializeSizes ===============================================
* Abstract:
* The sizes information is used by Simulink to determine the S-function
* block's characteristics (number of inputs, outputs, states, etc.).
*/
static void mdlInitializeSizes(SimStruct *S)
{
int_T nContStates;
int_T nCoeffs;
/* See sfuntmpl.doc for more details on the macros below. */
ssSetNumSFcnParams(S, NPARAMS); /* Number of expected parameters. */
#if defined(MATLAB_MEX_FILE)
if (ssGetNumSFcnParams(S) == ssGetSFcnParamsCount(S)) {
mdlCheckParameters(S);
if (ssGetErrorStatus(S) != NULL) {
return;
}
} else {
return; /* Parameter mismatch will be reported by Simulink. */
}
#endif
/*
* Define the characteristics of the block:
*
* Number of continuous states: length of denominator - 1
* Inputs port width 2 * (NumContStates+1) + 1
* Output port width 1
* DirectFeedThrough: 0 (Although this should be computed.
* We'll assume coefficients entered
* are strictly proper).
* Number of sample times: 2 (continuous and discrete)
* Number of Real work elements: 4*NumCoeffs
* (Two banks for num and den coeff's:
* NumBank0Coeffs
* DenBank0Coeffs