Build a Graph in CSR-like Format — build

Constructs a graph using a 1D-array-based Compressed Sparse Row (CSR) format. This structure is highly optimized for fast traversal in algorithms like Dijkstra's. Separating the graph construction from the path-finding algorithm avoids redundant processing when running algorithms multiple times on the same graph.

Usage

build_graph(n, u, v, w, directed = FALSE)

Arguments

n: an integer specifying the number of nodes (vertices) in the graph.
u: an integer vector of the starting nodes for each edge (1-indexed).
v: an integer vector of the ending nodes for each edge (1-indexed).
w: a numeric vector of edge weights (costs).
directed: a logical value indicating whether the graph is directed. Defaults to FALSE (undirected).

Value

build_graph() returns a list containing the internal graph representation (n, head, to, weight, nxt, and alloc_size).

Examples

n <- 4
u <- c(1, 1, 2, 3)
v <- c(2, 3, 4, 4)
w <- c(2, 5, 1, 3)
graph <- build_graph(n, u, v, w)