Y interpolate(const X&x) const {
if (mElements.size() == 0) return Y();
typename std::vector<element_type>::const_iterator it;
it = std::lower_bound(mElements.begin(), mElements.end(), element_type(x));
if (it != mElements.begin()) {
it--;
}
return it->eval(x);
}
/* Evaluate at multiple locations, assuming xx is sorted ascending */
std::vector<Y> interpolate(const std::vector<X>& xx) const {
if (mElements.size() == 0) return std::vector<Y>(xx.size());
typename std::vector<X>::const_iterator it;
typename std::vector<element_type>::const_iterator it2;
it2 = mElements.begin();
std::vector<Y> ys;
for (it = xx.begin(); it != xx.end(); it++) {
it2 = std::lower_bound(it2, mElements.end(), element_type(*it));
if (it2 != mElements.begin()) {
it2--;
}
ys.push_back(it2->eval(*it));
}
return ys;
}