Class NeighborsView¶

template <typename TSeq>

Non-allocating range over an agent's neighbors. More...

#include <agent-bones.hpp>

Classes¶

Type	Name
class	iterator

Public Functions¶

Type	Name
	NeighborsView () = default
	NeighborsView (const size_t * first, size_t n, std::vector< Agent< TSeq > > * pop)
Agent< TSeq > *	agent (size_t k) const
iterator	begin () const
bool	empty () const
iterator	end () const
size_t	id (size_t k) const
const size_t *	ids () const
size_t	size () const

Detailed Description¶

Agent::get_neighbors() builds and returns a std::vector of pointers, which costs a heap allocation on every call and it is called once per susceptible agent per day, in the innermost loop of every state-update function. This view iterates the agent's neighbor ids in place and resolves each one against the model's population as it goes, so the same loop runs without allocating:

for (auto * neighbor : p->neighbors_view(*m))
    ...

The order is the agent's neighbor order, identical to get_neighbors(). The view borrows from the agent and the model, so it must not outlive either, and it is invalidated by anything that changes the agent's ties.

Template parameters:

TSeq Sequence type (should match TSeq across the model)

Public Functions Documentation¶

function NeighborsView [1/2]¶

NeighborsView::NeighborsView () = default

function NeighborsView [2/2]¶

inline NeighborsView::NeighborsView (
    const size_t * first,
    size_t n,
    std::vector< Agent < TSeq > > * pop
)

function agent¶

inline Agent < TSeq > * NeighborsView::agent (
    size_t k
) const

The k-th neighbor.

Exception:

std::out_of_range if k >= size().

function begin¶

inline iterator NeighborsView::begin () const

function empty¶

inline bool NeighborsView::empty () const

function end¶

inline iterator NeighborsView::end () const

function id¶

inline size_t NeighborsView::id (
    size_t k
) const

Id of the k-th neighbor, without touching the neighbor's Agent.

Exception:

std::out_of_range if k >= size().

function ids¶

inline const size_t * NeighborsView::ids () const

The ids of the size() neighbors, in order (like std::vector::data(): only valid for indices below size(); nullptr when there are none). For scans that must not touch the neighbors' Agents.

function size¶

inline size_t NeighborsView::size () const

The documentation for this class was generated from the following file include/epiworld/agent-bones.hpp