Source code for pml.utils.pandas_util

# Copyright (C) 2012 David Rusk
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"""
Utility functions for working with pandas datatypes, i.e. DataFrames and 
Series.

@author: drusk
"""

def get_indices_with_value(series, value):
    """
    Retrieves the indices of a pandas Series which have the specified value.
    
    Args:
      series: pandas.Series
        The series to search and retrieve indices from.
      value:
        The value to search for.
        
    Returns:
      indices: pandas.Index
        The indices which held the specified value.
    """
    return series.index[series == value]

def are_dataframes_equal(dataframe1, dataframe2):
    """
    Compares two pandas DataFrame objects to see if they are equal.
    
    Args:
      dataframe1: pandas.DataFrame
      dataframe2: pandas.DataFrame
      
    Returns:
      True if the DataFrames are identically-labeled and all elements are the 
      same.  False otherwise. 
    """
    try:
        # reduce 2d boolean array down to a single answer
        return (dataframe1 == dataframe2).all().all()
    except Exception:
        # pandas throws:
        # "Exception: Can only compare identically-labeled DataFrame objects"
        return False