02.rs

use polars_core::error::PolarsResult;
use polars_core::prelude::*;
use pyo3_polars_derive::polars_expr;

#[polars_expr(output_type=Int32)]
fn horizontal_product(series: &[Series], kwargs: Option<&str>) -> PolarsResult<Series> {
    let _ = kwargs;

    let mut acc = series[0].clone();
    for s in &series[1..] {
        acc = (&acc * s)?
    }
    Ok(acc)
}

fn main() {}