rust 如何在没有0填充的情况下解析带有日期和月份的日期字符串

您的Default使用错误的标志运行.您需要将exact设置为true:

...
    let options = StrpTimeOptions {
        fmt: Some("%-m/%-d/%Y".into()),
        date_dtype: DataType::Date,
        exact: true,
        ..Default::default()
    };
...

已测试包含填充的完整代码:

use polars::prelude::*;
use polars_lazy::dsl::StrpTimeOptions;
use polars_lazy::prelude::{col, IntoLazy, LazyFrame};

fn main() {
    let df = df![
        "x" => ["01/04/2011", "2/4/2011", "3/4/2011", "4/4/2011"],
        "y" => [1, 2, 3, 4],
    ]
    .unwrap();
    let lf: LazyFrame = df.lazy();

    let options = StrpTimeOptions {
        fmt: Some("%-m/%-d/%Y".into()),
        date_dtype: DataType::Date,
        exact: true,
        ..Default::default()
    };

    let res = lf
        .clone()
        .with_column(col("x").str().strptime(options).alias("new time"))
        .collect()
        .unwrap();

    println!("{:?}", res);
}

输出:

shape: (4, 3)
┌────────────┬─────┬────────────┐
│ x          ┆ y   ┆ new time   │
│ ---        ┆ --- ┆ ---        │
│ str        ┆ i32 ┆ date       │
╞════════════╪═════╪════════════╡
│ 01/04/2011 ┆ 1   ┆ 2011-01-04 │
├╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┤
│ 2/4/2011   ┆ 2   ┆ 2011-02-04 │
├╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┤
│ 3/4/2011   ┆ 3   ┆ 2011-03-04 │
├╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┤
│ 4/4/2011   ┆ 4   ┆ 2011-04-04 │
└────────────┴─────┴────────────┘