Orthogonal systems of idempotents are applicable to Physics, Chemistry
and other areas of Mathematics. Given a finite group G, and a set par
tition {[theta(1)], [theta(2)], ..., [theta(k)]} of G, we present a me
thod that is sometimes successful in constructing a system of orthogon
al idempotents that are constant on {[theta(1)], [theta(2)], ..., [the
ta(k)]}. The functions are an extension of the irreducible character o
f finite group. (C) 1998 Elsevier Science Inc. All rights reserved.