graphrs 0.7.0

graphrs is a Rust package for the creation, manipulation and analysis of graphs.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170

use std::cmp::{Ord, Ordering, PartialOrd};
use std::fmt;
use std::fmt::{Debug, Display};
use std::hash::{Hash, Hasher};

/**
Represents a graph edge as (`u`, `v`).

Also allows `attributes`, as a `HashMap`, to be stored on an edge.
*/
#[derive(Clone)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Edge<T, A>
where
    T: PartialOrd + Send,
{
    /// The name of the first node of the edge.
    pub u: T,
    /// The name of the second node of the edge.
    pub v: T,
    /// Any attributes of the edge.
    pub attributes: Option<A>,
    /// The edge weight. For weighted `Graph` this should be a real number.
    /// For an unweighted `Graph` this should be `f64:NAN`.
    pub weight: f64,
}

impl<T, A> Edge<T, A>
where
    T: Eq + Clone + PartialOrd + Ord + Hash + Send + Sync + Display,
    A: Clone,
{
    /**
    Creates a new `Edge` with no attributes.

    # Arguments

    * `u`: The name of the first node of the edge.
    * `v`: The name of the second node of the edge.

    # Examples

    ```
    use graphrs::Edge;
    let edges = vec![
        Edge::<&str, ()>::new("n1", "n2"),
        Edge::<&str, ()>::new("n2", "n1"),
    ];
    ```
    */
    pub fn new(u: T, v: T) -> Edge<T, A> {
        Edge {
            u,
            v,
            attributes: None,
            weight: f64::NAN,
        }
    }

    /**
    Returns (v, u) if u > v.

    ```
    use graphrs::Edge;
    let edge1 = Edge::<&str, ()>::new("n2", "n1");
    let edge2 = edge1.ordered();
    assert_eq!(edge2.u, "n1");
    assert_eq!(edge2.v, "n2");
    ```
    */
    pub fn ordered(self: Edge<T, A>) -> Edge<T, A> {
        match self.u > self.v {
            true => self.reversed(),
            false => self,
        }
    }

    /**
    Reverses the edge. (u, v) -> (v, u)
    ```
    use graphrs::Edge;
    let edge1 = Edge::<&str, ()>::new("n2", "n1");
    let edge2 = edge1.reversed();
    assert_eq!(edge2.u, "n1");
    assert_eq!(edge2.v, "n2");
    ```
    */
    pub fn reversed(self: Edge<T, A>) -> Edge<T, A> {
        Edge {
            u: self.v,
            v: self.u,
            ..self
        }
    }

    /**
    Creates a (`u`, `v`) `Edge` with a specified `weight`.

    # Arguments

    * `u`: The name of the first node of the edge.
    * `v`: The name of the second node of the edge.
    * `weight`: The weight of the edge.

    # Examples

    ```
    use graphrs::Edge;
    let edges = vec![
        Edge::<&str, ()>::with_weight("n1", "n2", 1.0),
        Edge::<&str, ()>::with_weight("n2", "n1", 2.0),
    ];
    ```
    */
    pub fn with_weight(u: T, v: T, weight: f64) -> Edge<T, A> {
        Edge {
            u,
            v,
            attributes: None,
            weight,
        }
    }
}

impl<T: PartialEq + PartialOrd + Send + Sync, A> PartialEq for Edge<T, A> {
    fn eq(&self, other: &Self) -> bool {
        self.u == other.u && self.v == other.v
    }
}

impl<T: Eq + PartialOrd + Send + Sync, A> Eq for Edge<T, A> {}

impl<T: Debug + PartialOrd + Send + Sync, A> fmt::Debug for Edge<T, A> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Node")
            .field("u", &self.u)
            .field("v", &self.v)
            .finish()
    }
}

impl<T: Display + PartialOrd + Send + Sync, A> fmt::Display for Edge<T, A> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "({}, {})", self.u, self.v)
    }
}

impl<T: Hash + PartialOrd + Send + Sync, A> Hash for Edge<T, A> {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.u.hash(state);
        self.v.hash(state);
    }
}

impl<T: Eq + PartialEq + PartialOrd + Send + Sync, A> PartialOrd for Edge<T, A> {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl<T: Eq + PartialOrd + Send + Sync, A> Ord for Edge<T, A> {
    fn cmp(&self, other: &Self) -> Ordering {
        let u_cmp = self.u.partial_cmp(&other.u).unwrap();
        match u_cmp {
            Ordering::Equal => self.v.partial_cmp(&other.v).unwrap(),
            Ordering::Greater => u_cmp,
            Ordering::Less => u_cmp,
        }
    }
}