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foapy.characteristics.ma.geometric_mean

geometric_mean(intervals, dtype=None)

Calculates average geometric values of the intervals grouped by congeneric sequence.

\[ \left[ \Delta_{g_j} \right]_{1 \le j \le m} = \left[ \left( \prod_{i=1}^{n_j} \Delta_{ij} \right)^{1/n_j} \right]_{1 \le j \le m} \]

where \( \Delta_{ij} \) represents \(i\)-th interval of \(j\)-th congeneric intervals array, \( n_j \) is the total number of intervals in \(j\)-th congeneric intervals array and \(m\) is number of congeneric intervals arrays.

Parameters:

Name Type Description Default

intervals

array_like

An array of congeneric intervals array

required

dtype

dtype

The dtype of the output

None

Returns:

Type Description
array

An array of the geometric means of congeneric intervals.

Examples:

Calculate the geometric means of a sequence.

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import foapy
import numpy as np

source = np.array(['a', 'b', 'a', 'c', 'a', 'd'])
order = foapy.ma.order(source)
intervals = foapy.ma.intervals(order, foapy.binding.start, foapy.mode.normal)
result = foapy.characteristics.ma.geometric_mean(intervals)
print(result)
# [1.58740105 2.         4.         6.        ]

Calculate the arithmetic means of congeneric intervals of a sequence.

import foapy

X = []
X.append([1, 1, 4, 4])
X.append([3, 1, 3])
X.append([5, 3, 1])

result = foapy.characteristics.ma.geometric_mean(X)
print(result)
# [2.         2.08008382 2.46621207]
Source code in .tox/docs-deploy/lib/python3.11/site-packages/foapy/characteristics/ma/_geometric_mean.py
def geometric_mean(intervals, dtype=None):
    """
    Calculates average geometric values of the intervals grouped by congeneric sequence.

    $$
    \\left[ \\Delta_{g_j} \\right]_{1 \\le j \\le m} =
    \\left[
    \\left( \\prod_{i=1}^{n_j} \\Delta_{ij} \\right)^{1/n_j}
    \\right]_{1 \\le j \\le m}
    $$

    where \\( \\Delta_{ij} \\) represents $i$-th interval of $j$-th
    congeneric intervals array, \\( n_j \\) is the total
    number of intervals in $j$-th congeneric intervals array
    and $m$ is number of congeneric intervals arrays.

    Parameters
    ----------
    intervals : array_like
        An array of congeneric intervals array
    dtype : dtype, optional
        The dtype of the output

    Returns
    -------
    : array
        An array of the geometric means of congeneric intervals.

    Examples
    --------

    Calculate the geometric means of a sequence.

    ``` py linenums="1"
    import foapy
    import numpy as np

    source = np.array(['a', 'b', 'a', 'c', 'a', 'd'])
    order = foapy.ma.order(source)
    intervals = foapy.ma.intervals(order, foapy.binding.start, foapy.mode.normal)
    result = foapy.characteristics.ma.geometric_mean(intervals)
    print(result)
    # [1.58740105 2.         4.         6.        ]
    ```

    Calculate the arithmetic means of congeneric intervals of a sequence.

    ``` py linenums="1"
    import foapy

    X = []
    X.append([1, 1, 4, 4])
    X.append([3, 1, 3])
    X.append([5, 3, 1])

    result = foapy.characteristics.ma.geometric_mean(X)
    print(result)
    # [2.         2.08008382 2.46621207]
    ```
    """  # noqa: W605
    return np.asanyarray(
        [
            (
                np.power(
                    2,
                    np.sum(np.log2(line, dtype=dtype), dtype=dtype) / len(line),
                    dtype=dtype,
                )  # noqa: E501 E261
                if len(line) != 0
                else 0
            )
            for line in intervals
        ]
    )