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

//! Custom errors returned from our methods and functions.
use noisy_float::types::N64;
use std::error::Error;
use std::fmt;

/// An error that indicates that the input array was empty.
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct EmptyInput;

impl fmt::Display for EmptyInput {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "Empty input.")
    }
}

impl Error for EmptyInput {}

/// An error computing a minimum/maximum value.
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum MinMaxError {
    /// The input was empty.
    EmptyInput,
    /// The ordering between a tested pair of values was undefined.
    UndefinedOrder,
}

impl fmt::Display for MinMaxError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            MinMaxError::EmptyInput => write!(f, "Empty input."),
            MinMaxError::UndefinedOrder => {
                write!(f, "Undefined ordering between a tested pair of values.")
            }
        }
    }
}

impl Error for MinMaxError {}

impl From<EmptyInput> for MinMaxError {
    fn from(_: EmptyInput) -> MinMaxError {
        MinMaxError::EmptyInput
    }
}

/// An error used by methods and functions that take two arrays as argument and
/// expect them to have exactly the same shape
/// (e.g. `ShapeMismatch` is raised when `a.shape() == b.shape()` evaluates to `False`).
#[derive(Clone, Debug, PartialEq)]
pub struct ShapeMismatch {
    pub first_shape: Vec<usize>,
    pub second_shape: Vec<usize>,
}

impl fmt::Display for ShapeMismatch {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(
            f,
            "Array shapes do not match: {:?} and {:?}.",
            self.first_shape, self.second_shape
        )
    }
}

impl Error for ShapeMismatch {}

/// An error for methods that take multiple non-empty array inputs.
#[derive(Clone, Debug, PartialEq)]
pub enum MultiInputError {
    /// One or more of the arrays were empty.
    EmptyInput,
    /// The arrays did not have the same shape.
    ShapeMismatch(ShapeMismatch),
}

impl MultiInputError {
    /// Returns whether `self` is the `EmptyInput` variant.
    pub fn is_empty_input(&self) -> bool {
        match self {
            MultiInputError::EmptyInput => true,
            _ => false,
        }
    }

    /// Returns whether `self` is the `ShapeMismatch` variant.
    pub fn is_shape_mismatch(&self) -> bool {
        match self {
            MultiInputError::ShapeMismatch(_) => true,
            _ => false,
        }
    }
}

impl fmt::Display for MultiInputError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            MultiInputError::EmptyInput => write!(f, "Empty input."),
            MultiInputError::ShapeMismatch(e) => write!(f, "Shape mismatch: {}", e),
        }
    }
}

impl Error for MultiInputError {}

impl From<EmptyInput> for MultiInputError {
    fn from(_: EmptyInput) -> Self {
        MultiInputError::EmptyInput
    }
}

impl From<ShapeMismatch> for MultiInputError {
    fn from(err: ShapeMismatch) -> Self {
        MultiInputError::ShapeMismatch(err)
    }
}

/// An error computing a quantile.
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum QuantileError {
    /// The input was empty.
    EmptyInput,
    /// The `q` was not between `0.` and `1.` (inclusive).
    InvalidQuantile(N64),
}

impl fmt::Display for QuantileError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            QuantileError::EmptyInput => write!(f, "Empty input."),
            QuantileError::InvalidQuantile(q) => {
                write!(f, "{:} is not between 0. and 1. (inclusive).", q)
            }
        }
    }
}

impl Error for QuantileError {}

impl From<EmptyInput> for QuantileError {
    fn from(_: EmptyInput) -> QuantileError {
        QuantileError::EmptyInput
    }
}