Calculate and appends ordinality to a dataframe

Ordinality.py

def appendOrdinality(df, columns, ascending, strictlyIncreasing=False):
    """
    Appends absolute and relative ordinality to a dataframe.
    Oridinality is the normalized position of a row in a sorted dataframe.
    
    df:
        Pandas DataFrame
    columns: 
        List of column names for to be used for sorting (e.g. ['prob_1'])
    ascending: 
        List of ascending True/False for each row
    strictlyIncreasing: 
        ordinality will increment even if two consecutive rows are the same
    
    === Example and Module Test ===
    
    rs = np.random.RandomState(9)
    dfTest = pd.DataFrame(columns=['prob_0', 'prob_1'])
    dfTest['prob_0'] = rs.randint(0, 10, 10) / 10
    dfTest['prob_1'] = rs.randint(0, 10, 10) / 10
    appendOrdinality(dfTest, ['prob_1', 'prob_0'], [False, True])
    dfTest
    """
    # Sort by prob_0 from low to high, since two consecutive values might be the same, also use prob_1 to sort
    df.sort_values(columns, ascending=ascending, inplace=True)
    df.reset_index(inplace=True, drop=True)
    # Create two columns
    df['ordinality'] = np.nan
    df['abs_ordinality'] = -1
    n = len(df)
    # Initiate the first row
    abs_ordinality = 0
    i = 0
    df.at[i, 'ordinality'    ] = abs_ordinality / n
    df.at[i, 'abs_ordinality'] = abs_ordinality
    # iterate from the second row
    for i in range(1, n):
        # condition to only increment abs_ordinality if two rows are not the same, i.e. increasing/decreasing
        conds = [( abs(df.at[i, columns[j]] - df.at[i - 1, columns[j]]) > 0) for j in range(len(columns))]
        if sum(conds) > 0 or strictlyIncreasing:
            abs_ordinality += 1
        # update elements
        df.at[i, 'ordinality'    ] = abs_ordinality / n
        df.at[i, 'abs_ordinality'] = abs_ordinality

rs = np.random.RandomState(9)
dfTest = pd.DataFrame(columns=['prob_0', 'prob_1'])
dfTest['prob_0'] = rs.randint(0, 10, 10) / 10
dfTest['prob_1'] = rs.randint(0, 10, 10) / 10
appendOrdinality(dfTest, ['prob_1', 'prob_0'], [False, True])
dfTest