astar: A* algorithm for shortest path finding.

In machow/astar-r: A* Algorithm for Finding Shortest Paths

Description

A* algorithm for shortest path finding.

Usage

astar(start, goal, cost_estimate, edge_distance, neighbors,
  is_goal_reached, hash_func = identity, search_node_env = NULL)

Arguments

start	beginning node
goal	ending node
cost_estimate	binary function of node, goal. Should return Lower bound guess of distance between them.
edge_distance	binary function of node, neighbor. Should return distance between them.
neighbors	function that takes a node and returns its neighbors as a list.
is_goal_reached	binary function of a node and the goal. Returns whether that node reached the goal.
hash_func	function that takes a node and returns something that can be used as the key in a list (e.g. a number, a string...).
search_node_env	custom environment to put node information in (may be useful for visualization).

Examples

 nodes <- list(
   A = c(B = 100, C = 20),
   C = c(D = 20),
   D = c(B = 20)
 )
 neighbors <- function(node) names(nodes[[node]])
 cost_estimate <- function(node, goal) 1
 edge_distance <- function(src, dst) nodes[[src]][dst]
 is_goal_reached <- function(node, goal) identical(node, goal)

 path <- astar('A', 'B', cost_estimate, edge_distance, neighbors, is_goal_reached)

machow/astar-r documentation built on May 12, 2019, 7:35 a.m.