polars_core/utils/
series.rs

1use std::rc::Rc;
2
3use crate::prelude::*;
4use crate::series::amortized_iter::AmortSeries;
5
6/// A utility that allocates an [`AmortSeries`]. The applied function can then use that
7/// series container to save heap allocations and swap arrow arrays.
8pub fn with_unstable_series<F, T>(dtype: &DataType, f: F) -> T
9where
10    F: Fn(&mut AmortSeries) -> T,
11{
12    let container = Series::full_null(PlSmallStr::EMPTY, 0, dtype);
13    let mut us = AmortSeries::new(Rc::new(container));
14
15    f(&mut us)
16}
17
18pub fn is_deprecated_cast(input_dtype: &DataType, output_dtype: &DataType) -> bool {
19    use DataType as D;
20
21    #[allow(clippy::single_match)]
22    match (input_dtype, output_dtype) {
23        #[cfg(feature = "dtype-struct")]
24        (D::Struct(l_fields), D::Struct(r_fields)) => {
25            l_fields.len() != r_fields.len()
26                || l_fields
27                    .iter()
28                    .zip(r_fields.iter())
29                    .any(|(l, r)| l.name() != r.name() || is_deprecated_cast(l.dtype(), r.dtype()))
30        },
31        (D::List(input_dtype), D::List(output_dtype)) => {
32            is_deprecated_cast(input_dtype, output_dtype)
33        },
34        #[cfg(feature = "dtype-array")]
35        (D::Array(input_dtype, _), D::Array(output_dtype, _)) => {
36            is_deprecated_cast(input_dtype, output_dtype)
37        },
38        #[cfg(feature = "dtype-array")]
39        (D::List(input_dtype), D::Array(output_dtype, _))
40        | (D::Array(input_dtype, _), D::List(output_dtype)) => {
41            is_deprecated_cast(input_dtype, output_dtype)
42        },
43        _ => false,
44    }
45}
46
47pub fn handle_casting_failures(input: &Series, output: &Series) -> PolarsResult<()> {
48    // @Hack to deal with deprecated cast
49    // @2.0
50    if is_deprecated_cast(input.dtype(), output.dtype()) {
51        return Ok(());
52    }
53
54    let mut idxs = Vec::new();
55    input.find_validity_mismatch(output, &mut idxs);
56
57    // Base case. No strict casting failed.
58    if idxs.is_empty() {
59        return Ok(());
60    }
61
62    let num_failures = idxs.len();
63    let failures = input.take_slice(&idxs[..num_failures.min(10)])?;
64
65    let additional_info = match (input.dtype(), output.dtype()) {
66        (DataType::String, DataType::Date | DataType::Datetime(_, _)) => {
67            "\n\nYou might want to try:\n\
68            - setting `strict=False` to set values that cannot be converted to `null`\n\
69            - using `str.strptime`, `str.to_date`, or `str.to_datetime` and providing a format string"
70        },
71        #[cfg(feature = "dtype-categorical")]
72        (DataType::String, DataType::Enum(_, _)) => {
73            "\n\nEnsure that all values in the input column are present in the categories of the enum datatype."
74        },
75        _ if failures.len() < num_failures => {
76            "\n\nDid not show all failed cases as there were too many."
77        },
78        _ => "",
79    };
80
81    polars_bail!(
82        InvalidOperation:
83        "conversion from `{}` to `{}` failed in column '{}' for {} out of {} values: {}{}",
84        input.dtype(),
85        output.dtype(),
86        output.name(),
87        num_failures,
88        input.len(),
89        failures.fmt_list(),
90        additional_info,
91    )
92}
polars_core/utils/series.rs

polars_core/utils/
series.rs
