nu_command/math/
abs.rs

1use crate::math::utils::run_with_elementwise;
2use nu_engine::command_prelude::*;
3
4#[derive(Clone)]
5pub struct MathAbs;
6
7impl Command for MathAbs {
8    fn name(&self) -> &str {
9        "math abs"
10    }
11
12    fn signature(&self) -> Signature {
13        Signature::build("math abs")
14            .input_output_types(vec![
15                (Type::Number, Type::Number),
16                (Type::Duration, Type::Duration),
17                (Type::Filesize, Type::Filesize),
18                (
19                    Type::List(Box::new(Type::Number)),
20                    Type::List(Box::new(Type::Number)),
21                ),
22                (
23                    Type::List(Box::new(Type::Duration)),
24                    Type::List(Box::new(Type::Duration)),
25                ),
26                (
27                    Type::List(Box::new(Type::Filesize)),
28                    Type::List(Box::new(Type::Filesize)),
29                ),
30                (Type::Range, Type::List(Box::new(Type::Number))),
31                (Type::record(), Type::record()),
32            ])
33            .rest(
34                "columns",
35                SyntaxShape::CellPath,
36                "The cell-paths/columns to operate on.",
37            )
38            .allow_variants_without_examples(true)
39            .category(Category::Math)
40    }
41
42    fn description(&self) -> &str {
43        "Returns the absolute value of a number."
44    }
45
46    fn search_terms(&self) -> Vec<&str> {
47        vec!["absolute", "modulus", "positive", "distance"]
48    }
49
50    fn is_const(&self) -> bool {
51        true
52    }
53
54    fn run(
55        &self,
56        engine_state: &EngineState,
57        stack: &mut Stack,
58        call: &Call,
59        input: PipelineData,
60    ) -> Result<PipelineData, ShellError> {
61        let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
62        let head = call.head;
63        run_with_elementwise(
64            input,
65            cell_paths,
66            head,
67            engine_state.signals(),
68            false,
69            move |value| abs_helper(value, head),
70        )
71    }
72
73    fn run_const(
74        &self,
75        working_set: &StateWorkingSet,
76        call: &Call,
77        input: PipelineData,
78    ) -> Result<PipelineData, ShellError> {
79        let cell_paths: Vec<CellPath> = call.rest_const(working_set, 0)?;
80        let head = call.head;
81        run_with_elementwise(
82            input,
83            cell_paths,
84            head,
85            working_set.permanent().signals(),
86            false,
87            move |value| abs_helper(value, head),
88        )
89    }
90
91    fn examples(&self) -> Vec<Example<'_>> {
92        vec![
93            Example {
94                description: "Compute absolute value of each number in a list of numbers.",
95                example: "[-50 -100.0 25] | math abs",
96                result: Some(Value::list(
97                    vec![
98                        Value::test_int(50),
99                        Value::test_float(100.0),
100                        Value::test_int(25),
101                    ],
102                    Span::test_data(),
103                )),
104            },
105            Example {
106                description: "Compute the absolute value of list-valued columns in a record.",
107                example: "{alice: [-1 -2 -3], bob: [-4 -5]} | math abs",
108                result: Some(Value::test_record(record! {
109                    "alice" => Value::list(
110                        vec![Value::test_int(1), Value::test_int(2), Value::test_int(3)],
111                        Span::test_data(),
112                    ),
113                    "bob" => Value::list(
114                        vec![Value::test_int(4), Value::test_int(5)],
115                        Span::test_data(),
116                    ),
117                })),
118            },
119            Example {
120                description: "Compute the absolute value of a single column using a cell path.",
121                example: "{alice: [-1 -2 -3], bob: [-4 -5]} | math abs alice",
122                result: Some(Value::test_record(record! {
123                    "alice" => Value::list(
124                        vec![Value::test_int(1), Value::test_int(2), Value::test_int(3)],
125                        Span::test_data(),
126                    ),
127                    "bob" => Value::list(
128                        vec![Value::test_int(-4), Value::test_int(-5)],
129                        Span::test_data(),
130                    ),
131                })),
132            },
133        ]
134    }
135}
136
137fn abs_helper(val: Value, head: Span) -> Value {
138    let span = val.span();
139    match val {
140        Value::Int { val, .. } => match val.checked_abs() {
141            Some(abs) => Value::int(abs, span),
142            None => Value::error(
143                ShellError::OperatorOverflow {
144                    msg: "absolute value operation overflowed".into(),
145                    span,
146                    help: Some(format!(
147                        "the absolute value of {val} cannot be represented as a 64-bit integer"
148                    )),
149                },
150                span,
151            ),
152        },
153        Value::Float { val, .. } => Value::float(val.abs(), span),
154        Value::Duration { val, .. } => match val.checked_abs() {
155            Some(abs) => Value::duration(abs, span),
156            None => Value::error(
157                ShellError::OperatorOverflow {
158                    msg: "absolute value operation overflowed".into(),
159                    span,
160                    help: Some(
161                        "the absolute value of the minimum duration cannot be represented".into(),
162                    ),
163                },
164                span,
165            ),
166        },
167        Value::Filesize { val, .. } => match val.get().checked_abs() {
168            Some(abs) => Value::filesize(abs, span),
169            None => Value::error(
170                ShellError::OperatorOverflow {
171                    msg: "absolute value operation overflowed".into(),
172                    span,
173                    help: Some(
174                        "the absolute value of the minimum filesize cannot be represented".into(),
175                    ),
176                },
177                span,
178            ),
179        },
180        Value::Error { .. } => val,
181        other => Value::error(
182            ShellError::OnlySupportsThisInputType {
183                exp_input_type: crate::math::utils::NUMERIC_INPUT_TYPES.into(),
184                wrong_type: other.get_type().to_string(),
185                dst_span: head,
186                src_span: other.span(),
187            },
188            head,
189        ),
190    }
191}
192
193#[cfg(test)]
194mod test {
195    use super::*;
196
197    #[test]
198    fn test_examples() -> nu_test_support::Result {
199        nu_test_support::test().examples(MathAbs)
200    }
201}
nu_command/math/abs.rs

nu_command/math/
abs.rs
