Hi Estefan
the correct script to apply force (not stress) to the node is: setnode("xforce",nodeID,value)
but before that, I recommend you to use this command to get the node id at specific location: nodeID= getnode("idatpoint", xp, yp)
so it should look like this:
var xp = 0
var yp = 0
nodeID= getnode("idatpoint", xp, yp)
var forceValue = 1000;
setnode("xforce",nodeID,forceValue)
I did not check the script above so apologize if there is any syntax error but I hope you get the concept.
On the other hand, you always can mix the commands with scripting language for instance you will be able to use "applybc" command and directly apply normal stress to the edges.
applybc("nstress",-100.0,"xlim",-1,1,"ylim",-2,2)
it's going to apply constant distributed stress to individual edge. if you want to have variable stress you can use the same command multiple times for small range that covers single edge and repeat the sequence (or put it in the for loop) and increase the value as you move along.
Hopefully I could provide useful information. Please let me know if you face any issue/bug using any of these concepts.
Roozbeh