Given two finite subsets A, B of R-k (of C-k) we test in time (e(k4) n
l)(O(1)) whether there exists an isometry f of R-k (resp. of C-k) such
that f(A) = B where n is the maximum of the cardinalities of A and B,
and I is the maximum size of a vector belonging to A boolean OR B. In
contrast to the trivial (n(k) l)(O(1))-test, our algorithm is polynom
ial time not only for a fixed Fe bur also for k = O((4) root log n). (
C) 1997 Published by Elsevier Science B.V.