nushell/crates/nu-command/src/math/avg.rs
Jérémy Audiger a5c604c283
Uniformize usage() and extra_usage() message ending for commands helper. (#8268)
# Description

Working on uniformizing the ending messages regarding methods usage()
and extra_usage(). This is related to the issue
https://github.com/nushell/nushell/issues/5066 after discussing it with
@jntrnr

# User-Facing Changes

None.

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
2023-02-28 21:33:02 -08:00

75 lines
2.0 KiB
Rust

use crate::math::reducers::{reducer_for, Reduce};
use crate::math::utils::run_with_function;
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Type, Value};
#[derive(Clone)]
pub struct SubCommand;
impl Command for SubCommand {
fn name(&self) -> &str {
"math avg"
}
fn signature(&self) -> Signature {
Signature::build("math avg")
.input_output_types(vec![(Type::List(Box::new(Type::Number)), Type::Number)])
.category(Category::Math)
}
fn usage(&self) -> &str {
"Returns the average of a list of numbers."
}
fn search_terms(&self) -> Vec<&str> {
vec!["average", "mean", "statistics"]
}
fn run(
&self,
_engine_state: &EngineState,
_stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
run_with_function(call, input, average)
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Compute the average of a list of numbers",
example: "[-50 100.0 25] | math avg",
result: Some(Value::test_float(25.0)),
}]
}
}
pub fn average(values: &[Value], span: Span, head: &Span) -> Result<Value, ShellError> {
let sum = reducer_for(Reduce::Summation);
let total = &sum(Value::int(0, *head), values.to_vec(), span, *head)?;
match total {
Value::Filesize { val, span } => Ok(Value::Filesize {
val: val / values.len() as i64,
span: *span,
}),
Value::Duration { val, span } => Ok(Value::Duration {
val: val / values.len() as i64,
span: *span,
}),
_ => total.div(*head, &Value::int(values.len() as i64, *head), *head),
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(SubCommand {})
}
}