vectrix 0.4.0

A stack-allocated matrix type implemented with const generics
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

//! Row and column slices of a matrix.

use core::iter::Sum;
use core::ops::{Deref, DerefMut, Mul};

use stride::Stride;

////////////////////////////////////////////////////////////////////////////////
// Row
////////////////////////////////////////////////////////////////////////////////

/// A row in a [`Matrix`][crate::Matrix].
#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
#[repr(transparent)]
pub struct Row<T, const M: usize, const N: usize> {
    data: Stride<T, M>,
}

impl<T, const M: usize, const N: usize> Row<T, M, N> {
    pub(crate) fn new(data: &[T]) -> &Self {
        // SAFETY: `Row` and `Stride` are both repr(transparent)
        unsafe { &*(data as *const [T] as *const Self) }
    }

    pub(crate) fn new_mut(data: &mut [T]) -> &mut Self {
        // SAFETY: `Row` and `Stride` are both repr(transparent)
        unsafe { &mut *(data as *mut [T] as *mut Self) }
    }
}

impl<T, const M: usize, const N: usize> Deref for Row<T, M, N> {
    type Target = Stride<T, M>;

    fn deref(&self) -> &Self::Target {
        &self.data
    }
}

impl<T, const M: usize, const N: usize> DerefMut for Row<T, M, N> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.data
    }
}

impl<T, U, const M: usize, const N: usize, const S: usize> PartialEq<Stride<U, S>> for Row<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &Stride<U, S>) -> bool {
        self.data.eq(other)
    }
}

impl<T, U, const M: usize, const N: usize> PartialEq<[U]> for Row<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &[U]) -> bool {
        self.data.eq(other)
    }
}

impl<T, U, const M: usize, const N: usize, const P: usize> PartialEq<[U; P]> for Row<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &[U; P]) -> bool {
        self.data.eq(other)
    }
}

////////////////////////////////////////////////////////////////////////////////
// Column
////////////////////////////////////////////////////////////////////////////////

/// A column in a [`Matrix`][crate::Matrix].
#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
#[repr(transparent)]
pub struct Column<T, const M: usize, const N: usize> {
    data: Stride<T, 1>,
}

impl<T, const M: usize, const N: usize> Column<T, M, N> {
    pub(crate) fn new(data: &[T]) -> &Self {
        // SAFETY: `Column` and `Stride` are both repr(transparent)
        unsafe { &*(data as *const [T] as *const Self) }
    }

    pub(crate) fn new_mut(data: &mut [T]) -> &mut Self {
        // SAFETY: `Column` and `Stride` are both repr(transparent)
        unsafe { &mut *(data as *mut [T] as *mut Self) }
    }
}

impl<T, const M: usize, const N: usize> Deref for Column<T, M, N> {
    type Target = Stride<T, 1>;

    fn deref(&self) -> &Self::Target {
        &self.data
    }
}

impl<T, const M: usize, const N: usize> DerefMut for Column<T, M, N> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.data
    }
}

impl<T, U, const M: usize, const N: usize, const S: usize> PartialEq<Stride<U, S>>
    for Column<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &Stride<U, S>) -> bool {
        self.data.eq(other)
    }
}

impl<T, U, const M: usize, const N: usize> PartialEq<[U]> for Column<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &[U]) -> bool {
        self.data.eq(other)
    }
}

impl<T, U, const M: usize, const N: usize, const P: usize> PartialEq<[U; P]> for Column<T, M, N>
where
    T: PartialEq<U>,
{
    fn eq(&self, other: &[U; P]) -> bool {
        self.data.eq(other)
    }
}

////////////////////////////////////////////////////////////////////////////////
// General
////////////////////////////////////////////////////////////////////////////////

impl<T, const M: usize, const N: usize> Row<T, M, N> {
    /// Returns the dot product between a row and column.
    ///
    /// # Examples
    ///
    /// ```
    /// # use vectrix::{vector, row_vector};
    /// #
    /// let row_vector = row_vector![1, 2, 3];
    /// let row = row_vector.row(0);
    ///
    /// let column_vector = vector![4, 5, 6];
    /// let column = column_vector.column(0);
    ///
    /// assert_eq!(row.dot(column), 32);
    /// ```
    #[inline]
    pub fn dot<const P: usize>(&self, other: &Column<T, N, P>) -> T
    where
        T: Copy + Mul<Output = T> + Sum,
    {
        (0..N).map(|i| self[i] * other[i]).sum()
    }
}