Dear all, As discussed in ginac-list the function expand_dummy_sum is broken. A fix is now in CVS. The code was also rather horrible, so I fixed that too. I will also port this change to the 1.3-branch. I guess that there are no binary compatibility issues involved in making STLT protected, as explained below? Otherwise somebody has to complain and then I can remove the "protected:"-line again. Another thing: What is the idea of the answer to the question "I wish to mix matrices and indexed objects. How can that be done?"? I see a very strange expression there with three indices that are apparently contracted. However, we don't want to encourage our users to start typing that kind of garbage, do we? More changes: * Removed the remark from the tutorial that scalar_products can be used for tensors of a rank greater then one. * Made the declaration of STLT in container.h protected. It can be quite useful to have access to this when writing derived types. * Improved comments and an error message. Best wishes, Chris