dataframely — A declarative, 🐻❄️-native data frame validation library
🗂 Table of Contents
📖 Introduction
Dataframely is a Python package to validate the schema and content of polars data frames. Its
purpose is to make data pipelines more robust by ensuring that data meets expectations and more readable by adding
schema information to data frame type hints.
💿 Installation
You can install dataframely using your favorite package manager, e.g., pixi or pip:
pixi add dataframely
pip install dataframely
🎯 Usage
Defining a data frame schema
import dataframely as dy
import polars as pl
class HouseSchema(dy.Schema):
zip_code = dy.String(nullable=False, min_length=3)
num_bedrooms = dy.UInt8(nullable=False)
num_bathrooms = dy.UInt8(nullable=False)
price = dy.Float64(nullable=False)
@dy.rule()
def reasonable_bathroom_to_bedroom_ratio(cls) -> pl.Expr:
ratio = pl.col("num_bathrooms") / pl.col("num_bedrooms")
return (ratio >= 1 / 3) & (ratio <= 3)
@dy.rule()
def minimum_zip_code_count(cls) -> pl.Expr:
return (pl.len() >= 2).over("zip_code")
Validating data against schema
import polars as pl
df = pl.DataFrame(
{
"zip_code": ["01234", "01234", "1", "213", "123", "213"],
"num_bedrooms": [2, 2, 1, None, None, 2],
"num_bathrooms": [1, 2, 1, 1, 0, 8],
"price": [100_000, 110_000, 50_000, 80_000, 60_000, 160_000],
}
)
# Validate the data and cast columns to expected types
validated_df: dy.DataFrame[HouseSchema] = HouseSchema.validate(df, cast=True)
See more advanced usage examples in the documentation.
Metadata
Release files for dataframely 3.1.2
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| dataframely-3.1.2.tar.gz | 437.3 kB | Details |
Built distributions (wheels)
| File | Reset | |||
|---|---|---|---|---|
| dataframely-3.1.2-cp310-abi3-win_amd64.whl | CPython 3.10 | abi3 | Windows x86-64 | Details |
| dataframely-3.1.2-cp310-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl | CPython 3.10 | abi3 | Linux glibc 2.17+ x86-64 | Details |
| dataframely-3.1.2-cp310-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl | CPython 3.10 | abi3 | Linux glibc 2.17+ ARM64 | Details |
| dataframely-3.1.2-cp310-abi3-macosx_11_0_arm64.whl | CPython 3.10 | abi3 | macOS 11.0+ ARM64 | Details |
| dataframely-3.1.2-cp310-abi3-macosx_10_12_x86_64.whl | CPython 3.10 | abi3 | macOS 10.12+ x86-64 | Details |
Total release size: 42.5 MB
Release files / dataframely-3.1.2.tar.gz
| Download URL | dataframely-3.1.2.tar.gz |
|---|---|
| Size | 437.3 kB |
| Tags | Source |
|
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| Size | 8.9 MB |
| Tags | CPython 3.10 Windows x86-64 abi3 |
|
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|---|---|
| Size | 8.7 MB |
| Tags | CPython 3.10 Linux glibc 2.17+ x86-64 abi3 |
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|---|---|
| Size | 7.9 MB |
| Tags | CPython 3.10 abi3 macOS 11.0+ ARM64 |
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| Tags | CPython 3.10 abi3 macOS 10.12+ x86-64 |
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