(order)
return npix
Give the number of pixels for the given resolution order.

    Parameters
    ----------
    order : int
      the resolution order

    Returns
    -------
    npix : int
      corresponding number of pixels

    Notes
    -----
    A convenience function that successively applies order2nside then nside2npix to order.

    Examples
    --------
    >>> import healpy as hp
    >>> hp.order2npix(7)
    196608

    >>> print(hp.order2npix(np.arange(8)))
    [    12     48    192    768   3072  12288  49152 196608]

    >>> hp.order2npix(31)
    Traceback (most recent call last):
        ...
    ValueError: 2147483648 is not a valid nside parameter (must be a power of 2, less than 2**30)
Give the number of pixels for the given resolution order.
Give the number of pixels for the given resolution order .
def order2npix(order):
    """Give the number of pixels for the given resolution order.

    Parameters
    ----------
    order : int
      the resolution order

    Returns
    -------
    npix : int
      corresponding number of pixels

    Notes
    -----
    A convenience function that successively applies order2nside then nside2npix to order.

    Examples
    --------
    >>> import healpy as hp
    >>> hp.order2npix(7)
    196608

    >>> print(hp.order2npix(np.arange(8)))
    [    12     48    192    768   3072  12288  49152 196608]

    >>> hp.order2npix(31)
    Traceback (most recent call last):
        ...
    ValueError: 2147483648 is not a valid nside parameter (must be a power of 2, less than 2**30)
    """
    nside = order2nside(order)
    npix = nside2npix(nside)
    return npix
def order2npix ( order ) : nside = order2nside ( order ) npix = nside2npix ( nside ) return npix