Module constants 

Rust enumerations for igraph’s C constants (igraph_constants.h).

Each enum converts into the raw C value with From (e.g. igraph_neimode_t::from(NeighborMode::Out)), and back with TryFrom (an ErrorKind::InvalidValue error for values that are not part of the enumeration). All of them are re-exported by the prelude. Module-specific enums (e.g. layout or community options) live next to the functions that use them.

use igraph::{ffi, prelude::*};

// Out-neighbors follow the edge direction, in-neighbors go against it.
let g = Graph::from_edges(&[(0, 1), (2, 1), (1, 1)], 3, true).unwrap();
assert_eq!(g.neighbors(1, NeighborMode::Out).unwrap(), vec![1]);
assert_eq!(g.neighbors(1, NeighborMode::In).unwrap(), vec![0, 1, 2]);
assert_eq!(g.degree(1, NeighborMode::All, Loops::Twice).unwrap(), vec![4]);
assert_eq!(g.degree(1, NeighborMode::All, Loops::None).unwrap(), vec![2]);

// Conversions to and from the raw C constants.
assert_eq!(ffi::igraph_neimode_t::from(NeighborMode::In), ffi::igraph_neimode_t_IGRAPH_IN);
assert_eq!(NeighborMode::try_from(ffi::igraph_neimode_t_IGRAPH_ALL).unwrap(), NeighborMode::All);
assert!(Order::try_from(42 as ffi::igraph_order_t).is_err());

Enum	C type	Used by (for example)
NeighborMode	igraph_neimode_t	Graph::neighbors, Graph::degree, Graph::bfs, Graph::distances
Loops	igraph_loops_t	Graph::degree, Graph::neighbors_with, Graph::get_adjacency
EdgeTypeSw, AllowedEdgeTypes	igraph_edge_type_sw_t	Graph::rewire, Graph::erdos_renyi_game_gnm
Order	igraph_order_t	VectorInt::sort_ind, Graph::sort_vertex_ids_by_degree
Connectedness	igraph_connectedness_t	Graph::connected_components, Graph::is_connected
Reciprocity	igraph_reciprocity_t	Graph::reciprocity
Adjacency, GetAdjacency	igraph_adjacency_t, igraph_get_adjacency_t	Graph::adjacency, Graph::get_adjacency
StarMode, WheelMode, TreeMode	igraph_star_mode_t, igraph_wheel_mode_t, igraph_tree_mode_t	Graph::star, Graph::wheel, Graph::kary_tree
DegreeSequenceMethod, RealizeDegseq	igraph_degseq_t, igraph_realize_degseq_t	Graph::degree_sequence_game, Graph::realize_degree_sequence
RandomTreeMethod, BarabasiAlgorithm, ChungLuVariant	igraph_random_tree_t, igraph_barabasi_algorithm_t, igraph_chung_lu_t	Graph::tree_game, Graph::barabasi_game, Graph::chung_lu_game
EdgeOrder	igraph_edgeorder_type_t	EdgeSelector::AllOrdered
ToDirected, ToUndirected	igraph_to_directed_t, igraph_to_undirected_t	Graph::to_directed, Graph::to_undirected
VconnNei	igraph_vconn_nei_t	Graph::st_vertex_connectivity
SpincommUpdate, SpinglassImplementation, LpaVariant, CommunityComparison	igraph_spincomm_update_t, …	Graph::community_spinglass, Graph::community_label_propagation, compare_communities
TransitivityMode	igraph_transitivity_mode_t	Graph::transitivity_local_undirected
AddWeights	igraph_add_weights_t	NcolLglOptions
FasAlgorithm, FvsAlgorithm	igraph_fas_algorithm_t, igraph_fvs_algorithm_t	Graph::feedback_arc_set, Graph::feedback_vertex_set
SubgraphImplementation	igraph_subgraph_implementation_t	Graph::induced_subgraph
LayoutGrid	igraph_layout_grid_t	FruchtermanReingoldOptions
RandomWalkStuck, VoronoiTiebreaker	igraph_random_walk_stuck_t, igraph_voronoi_tiebreaker_t	Graph::random_walk, Graph::voronoi
MstAlgorithm, Product	igraph_mst_algorithm_t, igraph_product_t	Graph::minimum_spanning_tree, Graph::product
MatrixStorage	igraph_matrix_storage_t	raw FFI functions taking flat matrices

Structs

AllowedEdgeTypes

Which kinds of edges a graph may contain, as a set of flags (igraph_edge_type_sw_t, including the combination IGRAPH_LOOPS_SW | IGRAPH_MULTI_SW).

Enums

AddWeights

Whether to add weights when converting from matrices (igraph_add_weights_t).

Adjacency

How to interpret an adjacency matrix (igraph_adjacency_t).

BarabasiAlgorithm

Algorithm of the Barabási–Albert generator (igraph_barabasi_algorithm_t).

ChungLuVariant

Variant of the Chung–Lu model (igraph_chung_lu_t).

CommunityComparison

Measure used to compare two community structures (igraph_community_comparison_t).

Connectedness

Weak or strong connectedness (igraph_connectedness_t).

DegreeSequenceMethod

Method for sampling graphs with a given degree sequence (igraph_degseq_t).

EdgeOrder

Edge ordering for edge selectors (igraph_edgeorder_type_t).

EdgeTypeSw

Which kind of edges a random generator may produce (igraph_edge_type_sw_t).

FasAlgorithm

Feedback arc set algorithm (igraph_fas_algorithm_t).

FvsAlgorithm

Feedback vertex set algorithm (igraph_fvs_algorithm_t).

GetAdjacency

Which part of the adjacency matrix to produce for undirected graphs (igraph_get_adjacency_t).

LayoutGrid

Whether force-directed layouts use a grid (igraph_layout_grid_t).

Loops

How self-loops are counted (igraph_loops_t).

LpaVariant

Label propagation variant (igraph_lpa_variant_t).

MatrixStorage

Storage order of matrices given as flat arrays (igraph_matrix_storage_t).

MstAlgorithm

Minimum spanning tree algorithm (igraph_mst_algorithm_t).

NeighborMode

Which neighbors (or incident edges) to consider in directed graphs (igraph_neimode_t). Ignored for undirected graphs.

Order

Sorting order (igraph_order_t).

Product

Kind of graph product (igraph_product_t).

RandomTreeMethod

Random tree sampling algorithm (igraph_random_tree_t).

RandomWalkStuck

What a random walk does when stuck (igraph_random_walk_stuck_t).

RealizeDegseq

Vertex choice when realizing a degree sequence (igraph_realize_degseq_t).

Reciprocity

Reciprocity definition (igraph_reciprocity_t).

SpincommUpdate

Update rule of the spinglass community detection (igraph_spincomm_update_t).

SpinglassImplementation

Spinglass implementation (igraph_spinglass_implementation_t).

StarMode

Orientation of a star graph (igraph_star_mode_t).

SubgraphImplementation

Implementation strategy for induced subgraphs (igraph_subgraph_implementation_t).

ToDirected

How to convert undirected edges to directed ones (igraph_to_directed_t).

ToUndirected

How to convert directed edges to undirected ones (igraph_to_undirected_t).

TransitivityMode

Value of local transitivity for vertices of degree < 2 (igraph_transitivity_mode_t).

TreeMode

Orientation of a tree (igraph_tree_mode_t).

VconnNei

What to do when computing the vertex connectivity of two adjacent vertices, which no vertex removal can disconnect (igraph_vconn_nei_t).

VoronoiTiebreaker

Tie breaking in Voronoi partitioning (igraph_voronoi_tiebreaker_t).

WheelMode

Orientation of a wheel graph (igraph_wheel_mode_t).

Type Aliases

edge_type_sw_tDeprecated

Former name of EdgeTypeSw, kept for backwards compatibility.