I am trying to figure out, as I'm sure many newer FEMAP users do, how to effectively use layers and groups. I've read some posts on this site with differing recommendations. I'd like to use groups, but for some reason the entities in the groups will randomly add/remove entities without warning. Stray elements or nodes will just "show up" in there without my having done anything. I am diligent at making sure my automatic add is selected, but it still occurs.
I saw a post that this can be cleaned up with "group, operations, evalute" functionality. However, I'm not sure exactly what it is evaluating the group for. The commands manual just says that it "evaluates any number of selected groups." Evaluate for what, you dang book, for what?! Any help would be appreciated.
Groups were originally written to be rules based, i.e. in an organized FEA model, all the nodes, elements, properties, etc. at a particular geometric location were numbered in the same range, i.e. frame station 440 in an aircraft model would have nodes, elements, and properties numbered 440001, 440002, 440003.......
With this in mind, one could create group rules, i.e. Frame Station 440 Group Nodes 440001 to 440999, by 1. This way, whenever you added something with that ID it would automatically show up in the group. Evaluate was required back when machines were very slow, and re-evaluating what was in a group could take some time. Now, not so much. You can turn on Group, Operation, Evaluate Always, and pick all your groups and let this evaulation happen all the time, should not be that big a deal on most models.