[ansys_matt]

Hello,


The documentation says:


The index number can be used with the FNODE macro to obtain the global face node number (e.g.,node = FNODE(f,t,n)).

But this is not correct. I put this snippet in my udf:


begin_f_loop(f, tf)
{
f_node_loop(f, tf, n)
{
v = F_NODE(f, tf, n);

printf("The global node number is %i.\n",v);


And I only get nonsense printed out. My entire domain has 4232 nodes, so I expect to see numbers on [1,4232] printed to the console. I have tried using *v instead of v, but I still get numbers that are in the range of billions, not between 1 and 4232. How can I get the actual node number from within a UDF?


Thanks

[LuckyTran]

v is not a number but a reference to a Node dataclass. That's why it prints non-sense. You are seeing memory locations.

The local node number is actually n. I don't know how to get the global node number.

[ansys_matt]

I see. So when the manual says this is how to get the global node number, as I quoted, the manual is mistaken. That is awful.


Thanks for the reply. Maybe someone else will know how to do it.

[LuckyTran]

I'm not saying all hope is lost. The local node number is n. My macro's are rusty. As first step, what happens if you do?

printf("The local node number is %i.\n",n);


In serial cases that would be equivalent to the global node number anyway. In parallel cases, I don't recall how the threads are partitioned and how to collect them, or whether it is even necessary to collect them.

[ansys_matt]

Yeah, I do need the global node number, not just the local node. As I am using linear elements and looping over an edge, your code simply prints 1,2,1,2,1,2,1,2...

[eagle_001]

Hi, ansys_matt! Hope you have solved this problem.
I also tried to obtain the global index number of node by udf just as you did, but failed.
Thank you very much, ansys_matt!