Proportions of Different Unit-Cells in a Projection Lattice

A general formula for determinating the proportions of different unit-cells in a projection lattice is given. It is found that there exist certain relations between the occurrence frequency of a specified unit-cell in the aperiodic lattice and the projection (in a special subspace E^2') of the corresponding facets of the hyper-unit-cell of the n-dimensional periodic lattice. Based upon these, some special cases are discussed.