Pelage: Defensive analysis for Polars
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  • API Reference
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  1. API Reference
  • API Reference
  • Check functions
    • has_columns
    • has_dtypes
    • has_no_nulls
    • has_no_infs
    • unique
    • unique_combination_of_columns
    • accepted_values
    • not_accepted_values
    • accepted_range
    • maintains_relationships
    • column_is_within_n_std
    • custom_check
  • Checks with group_by
    • has_shape
    • at_least_one
    • not_constant
    • not_null_proportion
    • has_mandatory_values
    • mutually_exclusive_ranges
    • is_monotonic
  • Exceptions
    • PolarsAssertError

On this page

  • API Reference
    • Check functions
    • Checks with group_by
    • Exceptions

API Reference

Check functions

List of check functions.

has_columns Check if a DataFrame has the specified
has_dtypes Check that the columns have the expected types
has_no_nulls Check if a DataFrame has any null (missing) values.
has_no_infs Check if a DataFrame has any infinite (inf) values.
unique Check if there are no duplicated values in each one of the selected columns.
unique_combination_of_columns Ensure that the selected column have a unique combination per row.
accepted_values Raises error if columns contains values not specified in items
not_accepted_values Raises error if columns contains values specified in List of forbbiden items
accepted_range Check that all the values from specifed columns in the dict items are within the indicated range.
maintains_relationships Function to help ensuring that set of values in selected column remains the same in both DataFrames. This helps to maintain referential integrity.
column_is_within_n_std Function asserting values are within a given STD range, thus ensuring the absence of outliers.
custom_check Use custom Polars expression to check the DataFrame, based on .filter().

Checks with group_by

List of check functions with optional group_by option.

has_shape Check if a DataFrame has the specified shape.
at_least_one Ensure that there is at least one not null value in the designated columns.
not_constant Check if a DataFrame has constant columns.
not_null_proportion Checks that the proportion of non-null values in a column is within a a specified range [at_least, at_most] where at_most is an optional argument (default: 1.0).
has_mandatory_values Ensure that all specified values are present in their respective column.
mutually_exclusive_ranges Ensure that the specified columns contains no overlapping intervals.
is_monotonic Verify that values in a column are consecutively increasing or decreasing.

Exceptions

Types aliases and custom exceptions

PolarsAssertError Custom Error providing detailed information about the failed check.
has_columns