TheAlgorithms-Python

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"""
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Geometric Mean
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Reference :  https://en.wikipedia.org/wiki/Geometric_mean
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Geometric series
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Reference: https://en.wikipedia.org/wiki/Geometric_series
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"""
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def is_geometric_series(series: list) -> bool:
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    """
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    checking whether the input series is geometric series or not
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    >>> is_geometric_series([2, 4, 8])
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    True
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    >>> is_geometric_series([3, 6, 12, 24])
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    True
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    >>> is_geometric_series([1, 2, 3])
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    False
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    >>> is_geometric_series([0, 0, 3])
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    False
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    >>> is_geometric_series([])
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    Traceback (most recent call last):
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        ...
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    ValueError: Input list must be a non empty list
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    >>> is_geometric_series(4)
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    Traceback (most recent call last):
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        ...
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    ValueError: Input series is not valid, valid series - [2, 4, 8]
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    """
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    if not isinstance(series, list):
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        raise ValueError("Input series is not valid, valid series - [2, 4, 8]")
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    if len(series) == 0:
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        raise ValueError("Input list must be a non empty list")
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    if len(series) == 1:
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        return True
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    try:
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        common_ratio = series[1] / series[0]
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        for index in range(len(series) - 1):
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            if series[index + 1] / series[index] != common_ratio:
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                return False
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    except ZeroDivisionError:
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        return False
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    return True
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def geometric_mean(series: list) -> float:
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    """
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    return the geometric mean of series
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    >>> geometric_mean([2, 4, 8])
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    3.9999999999999996
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    >>> geometric_mean([3, 6, 12, 24])
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    8.48528137423857
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    >>> geometric_mean([4, 8, 16])
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    7.999999999999999
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    >>> geometric_mean(4)
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    Traceback (most recent call last):
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        ...
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    ValueError: Input series is not valid, valid series - [2, 4, 8]
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    >>> geometric_mean([1, 2, 3])
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    1.8171205928321397
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    >>> geometric_mean([0, 2, 3])
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    0.0
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    >>> geometric_mean([])
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    Traceback (most recent call last):
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        ...
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    ValueError: Input list must be a non empty list
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    """
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    if not isinstance(series, list):
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        raise ValueError("Input series is not valid, valid series - [2, 4, 8]")
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    if len(series) == 0:
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        raise ValueError("Input list must be a non empty list")
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    answer = 1
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    for value in series:
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        answer *= value
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    return pow(answer, 1 / len(series))
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if __name__ == "__main__":
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    import doctest
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    doctest.testmod()
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