Hi! On Wed, Aug 17, 2005 at 10:26:24AM +1000, John Pye wrote: > ex &x = myobject->getExpression(17); > x = x.subs(y==5); > > How would you suggest I did that? I suggest using a vector<ex> or a list<ex> instead of a GiNaC lst. Bye, Christian -- / Physics is an algorithm \/ http://www.uni-mainz.de/~bauec002/