def METHOD_NAME(x, y, center_x, center_y, r):
    """Azimuthal mask with =1 inside radius and =0 outside.
    :param x: x-coordinates (1d or 2d array numpy array)
    :param y: y-coordinates (1d or 2d array numpy array)
    :param center_x: center of azimuthal mask in x
    :param center_y: center of azimuthal mask in y
    :param r: radius of azimuthal mask
    :return: array with zeros outside r and ones inside azimuthal radius r
    :rtype: array of size of input grid with integers 0 or 1
    """
    x_shift = x - center_x
    y_shift = y - center_y
    R = np.sqrt(x_shift * x_shift + y_shift * y_shift)
    mask = np.empty_like(R, dtype="int")
    mask[R > r] = 0
    mask[R <= r] = 1
    return mask