nu_command/matrix/
identity.rs

1use crate::matrix::MatrixValue;
2use crate::matrix::value::positive_dim;
3use ndarray::ArrayD;
4use nu_engine::command_prelude::*;
5
6#[derive(Clone)]
7pub struct MatrixIdentity;
8
9impl Command for MatrixIdentity {
10    fn name(&self) -> &str {
11        "matrix identity"
12    }
13
14    fn signature(&self) -> Signature {
15        Signature::build("matrix identity")
16            .input_output_types(vec![(Type::Nothing, Type::Custom("matrix".into()))])
17            .required(
18                "size",
19                SyntaxShape::Int,
20                "The size of the square identity matrix.",
21            )
22            .category(Category::Filters)
23    }
24
25    fn description(&self) -> &str {
26        "Create an identity matrix of the given size."
27    }
28
29    fn search_terms(&self) -> Vec<&str> {
30        vec!["eye", "unit"]
31    }
32
33    fn run(
34        &self,
35        engine_state: &EngineState,
36        stack: &mut Stack,
37        call: &Call,
38        _input: PipelineData,
39    ) -> Result<PipelineData, ShellError> {
40        let head = call.head;
41        let size = positive_dim(call.req::<i64>(engine_state, stack, 0)?, head)?;
42
43        let mut array = ArrayD::zeros(vec![size, size]);
44        for i in 0..size {
45            array[[i, i]] = 1.0;
46        }
47        Ok(MatrixValue::new(array)
48            .into_value(head)
49            .into_pipeline_data())
50    }
51
52    fn examples(&self) -> Vec<Example<'static>> {
53        vec![
54            Example {
55                description: "Create a 3x3 identity matrix",
56                example: "matrix identity 3 | matrix into-nu | to nuon",
57                result: Some(Value::test_string(
58                    "[[1.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0, 1.0]]",
59                )),
60            },
61            Example {
62                description: "Create a 2x2 identity matrix",
63                example: "matrix identity 2 | matrix into-nu | to nuon",
64                result: Some(Value::test_string("[[1.0, 0.0], [0.0, 1.0]]")),
65            },
66        ]
67    }
68}
69
70#[cfg(test)]
71mod test {
72    use super::*;
73
74    #[test]
75    fn test_examples() -> nu_test_support::Result {
76        nu_test_support::test().examples(MatrixIdentity)
77    }
78}
nu_command/matrix/identity.rs

nu_command/matrix/
identity.rs
