DataTypeSystem

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This blog post proclaims and briefly describes the Python package “DataTypeSystem” that provides a type system for different data structures that are coercible into full arrays. The package is a Python translation of the Raku package “Data::TypeSystem”, [AAp1].

Installation

Install from GitHub

pip install -e git+https://github.com/antononcube/Python-packages.git#egg=DataTypeSystem-antononcube\&subdirectory=DataTypeSystem

From PyPi

pip install DataTypeSystem

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Usage examples

The type system conventions follow those of Mathematica’s Dataset — see the presentation “Dataset improvements”.

Here we get the Titanic dataset, change the “passengerAge” column values to be numeric, and show dataset’s dimensions:

import pandas dfTitanic = pandas.read_csv('https://raw.githubusercontent.com/mwaskom/seaborn-data/master/titanic.csv') dfTitanic = dfTitanic[["sex", "age", "pclass", "survived"]] dfTitanic = dfTitanic.rename(columns ={"pclass": "class"}) dfTitanic.shape

(891, 4)

Here is a sample of dataset’s records:

from DataTypeSystem import * dfTitanic.sample(3)

	sex	age	class	survived
555	male	62.0	1	0
278	male	7.0	3	0
266	male	16.0	3	0

Here is the type of a single record:

deduce_type(dfTitanic.iloc[12].to_dict())

Struct([age, class, sex, survived], [float, int, str, int])

Here is the type of single record’s values:

deduce_type(dfTitanic.iloc[12].to_dict().values())

Tuple([Atom(<class 'str'>), Atom(<class 'float'>), Atom(<class 'int'>), Atom(<class 'int'>)])

Here is the type of the whole dataset:

deduce_type(dfTitanic.to_dict())

Assoc(Atom(<class 'str'>), Assoc(Atom(<class 'int'>), Atom(<class 'str'>), 891), 4)

Here is the type of “values only” records:

valArr = dfTitanic.transpose().to_dict().values() deduce_type(valArr)

Vector(Struct([age, class, sex, survived], [float, int, str, int]), 891)

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References

[AAp1] Anton Antonov, Data::TypeSystem Raku package, (2023), GitHub/antononcube.