The following expression describes the Laue equation. Let Q = {q i } n i=1 , q i ∈ R 3 be a set of n points in reciprocal space and assume that there is a subset Q ⋆ ⊆ Q and three vectors a * , b * , c * ∈ R 3 being the crystal lattice basis vectors such that for each q ∈ Q ⋆ there exist integers h q , k q , l q ∈ Z such that the following (ideal) Laue condition is satisfied