k_anonymity.py

#!/usr/bin/env python
# coding: utf-8

# Author: Mandis Beigi
# Copyright (c) 2022 Medidata Solutions, Inc.
#
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# of this software and associated documentation files (the "Software"), to deal
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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import pandas as pd
import logging


#drop all rows with any column having less than k distinct values
def perform_k_anonymity(df, anonymity_k, ignore_columns):

    num_cols = df._get_numeric_data().columns
    cat_cols = list(set(df.columns) - set(num_cols))
    for ignore_column in ignore_columns:
        if ignore_column in cat_cols:
            cat_cols.remove(ignore_column)

    for column in cat_cols:
        removals = df[column].value_counts().reset_index()
        removals = removals[removals[column] >= anonymity_k]['index'].values
        df = df[df[column].isin(removals)]

    return(df)