Add multipucker action

[hainm]

Amber-MD/cpptraj#902

[hainm]

@PhiMykah

[hainm]

Please see the pucker function here:

pytraj/pytraj/all_actions.py

Lines 2244 to 2294 in 6d62181

	@register_pmap
	def pucker(traj=None,
	pucker_mask=("C1'", "C2'", "C3'", "C4'", "O4'"),
	resrange=None,
	top=None,
	dtype='dataset',
	range360=False,
	method='altona',
	use_com=True,
	amplitude=False,
	offset=None):
	"""compute pucker
	Parameters
	----------
	traj : Trajectory-like
	pucker_mask : str
	resrange : None or array of int
	top : Topology, optional
	dtype : str, return type
	range360: bool, use 360 or 180 scale
	method : {'altona', 'cremer'}, default 'altona'
	use_com : bool
	amplitude : bool, default False
	offset : None or float
	Returns
	-------
	Dataset
	"""
	top_ = get_topology(traj, top)
	if resrange is None:
	resrange = range(top_.n_residues)
	_range360 = "range360" if range360 else ""
	geom = "geom" if not use_com else ""
	amp = "amplitude" if amplitude else ""
	offset_ = "offset " + str(offset) if offset else ""
	c_dslist = CpptrajDatasetList()
	for res in resrange:
	command = " ".join((":" + str(res + 1) + '@' + x for x in pucker_mask))
	name = "pucker_res" + str(res + 1)
	command = " ".join((name, command, _range360, method, geom, amp,
	offset_))
	act = c_action.Action_Pucker()
	act(command, traj, top=top_, dslist=c_dslist)
	return get_data_from_dtype(c_dslist, dtype)

You could do similar to multipucker

[hainm]

pytraj/pytraj/actions/structure.py

Line 413 in e8ff455

def multipucker(traj=None,