Efficient Filtering of Pandas DataFrames and Series
Filtering data in Pandas DataFrames and Series is essential for data manipulation and analysis. To efficiently apply multiple filters, consider leveraging Pandas' built-in operators and boolean indexing.
For a DataFrame or Series, providing an operation and a list of values in a dictionary format, as shown in the example below:
<code class="python">relops = {'>=': [1], '<=': [1]}
To apply these filters:
<code class="python">import numpy as np def boolean_filter(x, relops): filters = [] for op, vals in relops.items(): op_func = getattr(np, op) for val in vals: filters.append(op_func(x, val)) return x[(np.logical_and(*filters))] ## Example: df = pandas.DataFrame({'col1': [0, 1, 2], 'col2': [10, 11, 12]}) result = boolean_filter(df['col1'], {'>=': [1]}) print(result) ## Output: # col1 # 1 1 # 2 2 # Name: col1</code>
By utilizing boolean indexing, this method avoids unnecessary copying and is highly efficient, especially for large datasets.
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