// predict a first estimate of the state at step end (P in the PECE sequence)
final double stepEnd = stepStart + stepSize;
interpolator.setInterpolatedTime(stepEnd);
final ExpandableStatefulODE expandable = getExpandable();
final EquationsMapper primary = expandable.getPrimaryMapper();
primary.insertEquationData(interpolator.getInterpolatedState(), yTmp);
int index = 0;
for (final EquationsMapper secondary : expandable.getSecondaryMappers()) {
secondary.insertEquationData(interpolator.getInterpolatedSecondaryState(index), yTmp);
++index;
}