for n being Nat
for RAS being non empty MidSp-like ReperAlgebraStr over n + 2
for a being Point of RAS
for p being Tuple of (n + 1),RAS
for W being ATLAS of RAS
for x being Tuple of (n + 1),W holds
( W . (a,p) = x iff (a,x) . W = p )