The most intuitively candidate is to use the decomposition matrix
: . By opposition with all the other methods
investigated here, this is an *a* *priori* reconstruction, since it
does not use and . It will be considered as our
reference method. Note that if the number of zeros is not constant in
each column of , it has been shown in [Mayoraz-Moreira] that
should be normalized as
.

Tue Mar 31 18:35:24 MET DST 1998