Access to a local stiffness matrix - possible modification of the gloobal matrix assembling process

Dear all,

I´d like to kindly ask you if you could tell me, if there exists a way how to ge the access to the global stiffness matrix assembling process in order to make some modifications. I don´t want to go much into details, just need to go further inside, not only getting the global stiffness matrix (or any other matrix possibly).

To be a bit more precise:

there´s a loop throughout all the finite elements

for 1:1:num_elems
create local matrix
"I want to get here..."
put the local matrix into global
end

I just need to be able to get into this loop and fiddle with those local matrices etc. I would be very grateful for any comments, tricks, ideas or even better, the solution. (Does it make any difference using 4.2a or higher version?)

Thank you and have a nice day!

Hrtus Rostislav, The Czech Republic