node

In CAE, we can apply the concretrated force on a picked node. However, if we want to use 
subroutine  to difine a complicated force, such as moving load, then we must refer to the COORDS of a point. Because we can use the COORDS of integration points other than nodes, then how to transfer the  node load to the integration points load? Any information will be appreciated.

User subroutine interface

Dear All,

I have much problem when modelling my project with ANSYS, one of problem that I met always like this 

 *** ERROR ***                           CP =     296.828   TIME= 14:56:15
 A small negative equation solver pivot term has been encountered at the
 ROTZ degree of freedom of node 11758.  Check for an insufficiently     
 constrained model.