[PPL-devel] assign a variable

[fersman at lsv.ens-cachan.fr]

Dear Roberto,

In my program I need to assign a variable, say x, a new value, say y+k, in
a polyhedron.
As far as I understand, to do this i need to free x, i.e. romove
constraints on x, and after that intersect with the constraint x==y+k.
Using functions from the library, a can first remove dimension x, then add
a new dimension and add a constraint. After that the representation of the
polyhedron when it is printed changes, i.e. if A represented x before, 
now it would represent y. How to avoid this problem? Is there a better way
of freeing a variable than removing the dimension and adding it again?

Best regards,
Elena