/**
* Form a new external, quantized state model (QSS-specific).
*
* @param stateIdx The state index.
*/
protected final void _triggerQuantizationEventWorker(final int stateIdx) {
// Note the superclass takes care of updating status variables and so on.
// Initialize.
final ModelPolynomial qStateMdl = _qStateMdls[stateIdx];
final ModelPolynomial cStateMdl = _cStateMdls[stateIdx];
final double dtStateMdl = _currSimTime.subtractToDouble(cStateMdl.tMdl);
// Update the external, quantized state model.
qStateMdl.tMdl = _currSimTime;
qStateMdl.coeffs[0] = cStateMdl.evaluate(dtStateMdl);
qStateMdl.coeffs[1] = cStateMdl.evaluateDerivative(dtStateMdl);
}
/** Form new internal, continuous state models (QSS-specific). */
protected final void _triggerRateEventWorker() throws Exception {
// Note the superclass takes care of updating status variables and so on.
// Get values, at {_currSimTime}, of arguments to derivative function.
// In general, expect the integrator formed all of its
// continuous state models at the same time. If so, can find a
// single delta-time, rather than having to find multiple differences
// from {_currSimTime}. Know that finding time differences is
// expensive in Ptolemy, so want to avoid doing that if possible.
// However, there is a chance that the continuous state models were
// formed at different times. For example:
// (1) User can reset a single state at any simulation time.
// (2) In future, might be possible to avoid updating a
// continuous state model if know none of its arguments changed.
Time tStateMdl = null;
double dtStateMdl = 0;
for (int ii = 0; ii < _stateCt; ++ii) {
final ModelPolynomial cStateMdl = _cStateMdls[ii];
// Check for different model time. Note testing object identity OK.
if (cStateMdl.tMdl != tStateMdl) {
tStateMdl = cStateMdl.tMdl;
dtStateMdl = _currSimTime.subtractToDouble(tStateMdl);
}
_stateVals_xx[ii] = cStateMdl.evaluate(dtStateMdl);
}
// In general, don't expect input variable models to have same times.
for (int ii = 0; ii < _ivCt; ++ii) {
_ivVals_xx[ii] = _ivMdls[ii].evaluate(_currSimTime);
}
// Evaluate derivative function at {_currSimTime}.
int retVal =
_derivFcn.evaluateDerivatives(_currSimTime, _stateVals_xx, _ivVals_xx, _stateDerivs_xx);
if (0 != retVal) {
throw new Exception("_derivFcn.evalDerivs() returned " + retVal);
}
// Update the internal, continuous state models.
// Note this is a partial update, since don't yet know the second
// derivatives. Do the update now so that, when find the sample point
// needed to estimate second derivatives, will be able to use as much
// current information about the continuous state as possible.
// This also updates the rate model, which is just the derivative of
// the state model.
for (int ii = 0; ii < _stateCt; ++ii) {
final ModelPolynomial cStateMdl = _cStateMdls[ii];
cStateMdl.tMdl = _currSimTime;
cStateMdl.coeffs[0] = _stateVals_xx[ii];
cStateMdl.coeffs[1] = _stateDerivs_xx[ii];
cStateMdl.coeffs[2] = 0;
}
// Choose a sample time, different from {_currSimTime}.
// For estimating second derivatives.
final double dtSampleFD = 1e-8 * Math.max(1, Math.abs(_currSimTime.getDoubleValue()));
double dtSample = Double.POSITIVE_INFINITY;
for (int ii = 0; ii < _stateCt; ++ii) {
final double derivii = _stateDerivs_xx[ii];
double dtii;
if (derivii != 0) {
dtii = _dqs[ii] / Math.abs(derivii);
} else {
dtii = dtSampleFD;
}
if (dtii < dtSample && dtii > 0.0) {
dtSample = dtii;
}
}
assert (dtSample > 0);
final Time tSample = _currSimTime.addUnchecked(dtSample);
// Get values, at {tSample}, of arguments to derivative function.
// Note that here, know all continous state models have same time.
// Therefore can use same delta-time for all evals.
for (int ii = 0; ii < _stateCt; ++ii) {
_stateVals_xx[ii] = _cStateMdls[ii].evaluate(dtSample);
}
for (int ii = 0; ii < _ivCt; ++ii) {
_ivVals_xx[ii] = _ivMdls[ii].evaluate(tSample);
}
// Evaluate derivative function at {tSample}.
retVal =
_derivFcn.evaluateDerivatives(tSample, _stateVals_xx, _ivVals_xx, _stateDerivsSample_xx);
if (0 != retVal) {
throw new Exception("_derivFcn.evalDerivs() returned " + retVal);
}
// Update the internal, continuous state models.
final double oneOverTwoDtSample = 0.5 / dtSample;
for (int ii = 0; ii < _stateCt; ++ii) {
_cStateMdls[ii].coeffs[2] =
oneOverTwoDtSample * (_stateDerivsSample_xx[ii] - _stateDerivs_xx[ii]);
}
}
