Provides the decomposition at a particular composition.

        Args:
            comp: A composition

        Returns:
            Decomposition as a dict of {Entry: amount}

def get_decomposition(self, comp):
        """
        Provides the decomposition at a particular composition.

        Args:
            comp: A composition

        Returns:
            Decomposition as a dict of {Entry: amount}
        """
        facet, simplex = self._get_facet_and_simplex(comp)
        decomp_amts = simplex.bary_coords(self.pd_coords(comp))
        return {self.qhull_entries[f]: amt
                for f, amt in zip(facet, decomp_amts)
                if abs(amt) > PhaseDiagram.numerical_tol}