def rgb_to_hex(rgb):
    """
    Convert an RGB color representation to a HEX color representation.
    (r, g, b) :: r -> [0.0, 1.0]
                 g -> [0.0, 1.0]
                 b -> [0.0, 1.0]
    :param rgb: A tuple of three numeric values corresponding to the red,
    green, and blue value.
    :return: HEX representation of the input RGB value.
    :rtype: str
    >>> rgb_to_hex((1.0, 0.0, 0.0))
    '#FF0000'
    """
    r, g, b = (k*255 for k in rgb)
    return "#{0}{1}{2}".format(
        *(hex(int(round(k)))[2:].zfill(2) for k in (r, g, b))
    ).upper()