def calcGeometricMean (theList):
    """Calculates the geometric mean of a list of values.

    :param theList: The list of which the geometric mean
    :type theList: list
    :return: The geometric mean of the values of theList
    :rtype: float
    """
    product = 1
    root = 0
    for value in theList:
        product *= value
        root += 1

    return product ** (1 / root)