3 examples of 'pandas agg' in Python

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def runAgg(spark, df):
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    df.agg(max("amount"), min("price")).show()
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    df.agg({"amount": "max", "price": "min"}).show()

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def agg_to_year(self, df, func='sum'):
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    """
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    Aggregate a DataFrame (cells x months) to (cells x years).
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    The groups are defined by an array the length of the number of columns,
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    where identical values are grouped. Integer division by 12 on the
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    column index gives sequential groups of length 12.
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    :param df:      DataFrame with months in columns
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    :param func:    Function to use for aggregation [default sum]
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    """
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    return df.groupby(np.arange(len(df.columns)) // NMONTHS, axis=1).agg(func)

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def test_aggregate_no_groups():
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    df = pd.DataFrame({
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        'df.g': [0, 0, 1, 1],
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        'df.a': [4, 5, 6, 7],
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    })
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    def _scalar_df(values):
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        return pd.DataFrame(values, index=[0])
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    def perform(q):
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        node = Aggregate(Literal(df), [DerivedColumn.parse(q)])
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        ex = PandasExecutor()
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        return ex.evaluate(node, None)
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    pdt.assert_frame_equal(perform('SUM(a) as c'), _scalar_df({'$0.c': 22}))
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    pdt.assert_frame_equal(perform('AVG(a) as c'), _scalar_df({'$0.c': 22 / 4.0}))
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    pdt.assert_frame_equal(perform('MIN(a) as c'), _scalar_df({'$0.c': 4}))
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    pdt.assert_frame_equal(perform('MAX(a) as c'), _scalar_df({'$0.c': 7}))
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    pdt.assert_frame_equal(perform('COUNT(a) as c'), _scalar_df({'$0.c': 4}))