Template Function lower_star_backwards

• Defined in File extension.hpp

Function Documentation

template<typename T>
std::vector<T> lower_star_backwards(const std::vector<std::vector<T>> &grad_dgms, const std::vector<std::vector<int>> &bdinds, const std::vector<std::vector<size_t>> &imap)

Helper function for computing a gradient on function that is extended in lower star filtration from gradient on persistence pairs

grad_dgms and bdinds should be flattened in each dimension grad_dgms[dim][k] is gradient of birth of pair k//2 grad_dgms[dim][k+1] is gradinet of death of pair k//2

Parameters

• grad_dgms – gradient of persistence diagrams

• bdinds – birth-death indices of each pair

• imap – map from simplices to critical vertex in filtration