Need example to calculate rolling_min using polars

help
1

I have been struggling with getting a working example of calculating a rolling minimum using polars (0.34.2). I would think something like the below code should work, but the latest version of polars doesn't want to accept an integer for window_size, it wants Duration instead, and I can't figure that part out. Does anyone have a working example that I can learn from? TIA.

    let df = df! {
        "Date" => &["2012-05-18", "2012-05-21", "2012-05-22", "2012-05-23"],
        "Low" => &[38.0, 34.0, 31.0, 32.0] 
    }.unwrap();

    let options = RollingOptions {
        window_size: 3,        // Window size
        min_periods: 1,        // Minimum number of observations in window required to have a value
        center: false,         // Set to true to set the labels at the center of the window
        weights: None,         // Optional weights for the window
        by: None,              // Optional Series to perform operation by
    };

    // Calculate rolling minimum
    let rolling_min = df.column("Low").unwrap().rolling_min(options).unwrap();

    // Print the result
    println!("Rolling minimum: {:?}", rolling_min);

rustexplorer

2

have you tried this?

// omitted code
    window_size: polars::prelude::Duration::new(3),
// ommited code
1 Like
3

https://pola-rs.github.io/polars/py-polars/html/reference/expressions/api/polars.Expr.rolling_min.html

rustexplorer

1 Like