nushell/crates/nu-command/src/dataframe/series/indexes/arg_unique.rs

92 lines
2.4 KiB
Rust

use super::super::super::values::{Column, NuDataFrame};
use nu_protocol::{
ast::Call,
engine::{Command, EngineState, Stack},
Category, Example, PipelineData, ShellError, Signature, Span, Type, Value,
};
use polars::prelude::IntoSeries;
#[derive(Clone)]
pub struct ArgUnique;
impl Command for ArgUnique {
fn name(&self) -> &str {
"arg-unique"
}
fn usage(&self) -> &str {
"Returns indexes for unique values"
}
fn signature(&self) -> Signature {
Signature::build(self.name())
.input_type(Type::Custom("dataframe".into()))
.output_type(Type::Custom("dataframe".into()))
.category(Category::Custom("dataframe".into()))
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Returns indexes for unique values",
example: "[1 2 2 3 3] | into df | arg-unique",
result: Some(
NuDataFrame::try_from_columns(vec![Column::new(
"arg_unique".to_string(),
vec![Value::test_int(0), Value::test_int(1), Value::test_int(3)],
)])
.expect("simple df for test should not fail")
.into_value(Span::test_data()),
),
}]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
command(engine_state, stack, call, input)
}
}
fn command(
_engine_state: &EngineState,
_stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let df = NuDataFrame::try_from_pipeline(input, call.head)?;
let mut res = df
.as_series(call.head)?
.arg_unique()
.map_err(|e| {
ShellError::GenericError(
"Error extracting unique values".into(),
e.to_string(),
Some(call.head),
None,
Vec::new(),
)
})?
.into_series();
res.rename("arg_unique");
NuDataFrame::try_from_series(vec![res], call.head)
.map(|df| PipelineData::Value(NuDataFrame::into_value(df, call.head), None))
}
#[cfg(test)]
mod test {
use super::super::super::super::test_dataframe::test_dataframe;
use super::*;
#[test]
fn test_examples() {
test_dataframe(vec![Box::new(ArgUnique {})])
}
}