def eval(self, jds = None, nostab = True):
		"""
		Evaluates the spline at jds, and returns the corresponding mags-like vector.
		By default, we exclude the stabilization points !
		If jds is not None, we use them instead of our own jds (in this case excludestab makes no sense)
		"""
		if jds is None:
			if nostab:
				jds = self.datapoints.jds[self.datapoints.mask]
			else:
				jds = self.datapoints.jds
		else:
			# A minimal check for non-extrapolation condition should go here !
			pass