A fundamental parallelepiped of a full-rank point lattice
with basis
is the half-open set
The translations for
form a set partition
of
,
so
is a fundamental domain for these translations.
The closure of
is the parallelepiped spanned
by the basis vectors. Different
bases of the point lattice
generally give different fundamental parallelepipeds, but all have the same volume,
namely the covolume of
.