feat: add weight handling documentation for graph generation functions

Author: elecbug

v2/graph/standard/barabasi_albert.go

@@ -9,6 +9,8 @@ import (
 // BarabasiAlbertGraph generates a graph based on the Barabási-Albert preferential attachment model.
 // The graph starts with m fully connected nodes, and new nodes are added one by one, each connecting
 // to m existing nodes with a probability proportional to their degree.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func BarabasiAlbertGraph(seed int, directed bool, weightFunc WeightedFunc, n int, m int) (*graph.Graph, error) {
 	if n < 0 {
 		return nil, fmt.Errorf("invalid number of nodes: n must be non-negative")

v2/graph/standard/common.go

@@ -45,6 +45,8 @@ func generateRand(seed int) *rand.Rand {
 }
 
 // StandardGraph generates a graph based on the provided configuration. It supports various graph types and parameters.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func StandardGraph(seed int, directed bool, weightFunc WeightedFunc, config GraphConfig) (*graph.Graph, error) {
 	switch config.Type {
 	case Grid:

v2/graph/standard/erdos_renyi.go

@@ -8,6 +8,8 @@ import (
 
 // ErdosRenyiGraph generates a random graph based on the Erdős-Rényi model.
 // Nodes are added first, and then edges are created between nodes with a probability p.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func ErdosRenyiGraph(seed int, directed bool, weightFunc WeightedFunc, n int, p float64) (*graph.Graph, error) {
 	if p < 0 || p > 1 {
 		return nil, fmt.Errorf("invalid probability: p must be between 0 and 1")

v2/graph/standard/grid.go

@@ -8,6 +8,8 @@ import (
 
 // GridGraph generates a grid graph with the specified number of rows and columns.
 // If torus is true, the graph will wrap around at the edges, creating a toroidal structure.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func GridGraph(seed int, directed bool, weightFunc WeightedFunc, rows, cols int, torus bool) (*graph.Graph, error) {
 	if rows < 0 || cols < 0 {
 		return nil, fmt.Errorf("rows and cols must be non-negative")

v2/graph/standard/random_geometric.go

@@ -10,6 +10,8 @@ import (
 // RandomGeometricGraph generates a random geometric graph (RGG).
 // Nodes are placed uniformly at random in the unit square, and edges
 // are added between nodes that are within a specified radius r.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func RandomGeometricGraph(seed int, directed bool, weightFunc WeightedFunc, n int, r float64) (*graph.Graph, error) {
 	if r < 0 || r > 1 {
 		return nil, fmt.Errorf("invalid radius: r must be between 0 and 1")

v2/graph/standard/random_regular.go

@@ -9,6 +9,8 @@ import (
 // RandomRegularGraph generates a random k-regular graph with n nodes.
 // Each node has exactly degree k. Returns nil if impossible.
 // This implementation requires n*k to be even.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func RandomRegularGraph(seed int, directed bool, weightFunc WeightedFunc, n, k int) (*graph.Graph, error) {
 	if k < 0 || k >= n {
 		// degree must be between 0 and n-1

v2/graph/standard/triangle_hex.go

@@ -7,6 +7,8 @@ import (
 )
 
 // TriangleHexGraph generates a hexagonal lattice graph with a specified edge length.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func TriangleHexGraph(seed int, directed bool, weightFunc WeightedFunc, edge int) (*graph.Graph, error) {
 
 	if edge < 0 {

v2/graph/standard/watts_strogatz.go

@@ -7,6 +7,8 @@ import (
 )
 
 // WattsStrogatzGraph generates a small-world graph based on the Watts-Strogatz model.
+// If weightFunc is nil, all edges will have no weight (unweighted graph). Otherwise, weightFunc will be called for
+// each new edge with the new node and the target node as arguments.
 func WattsStrogatzGraph(seed int, directed bool, weightFunc WeightedFunc, n, k int, beta float64) (*graph.Graph, error) {
 	if k < 0 || k >= n {
 		// degree must be between 0 and n-1