A developer/preview PrePoMax version v2.0.10 has been released

In this version:

  • Step controls editor was added (Right click on the step → Edit controls)
  • The op parameter for loads was changed to a separate keyword. This enables the user to insert op=mod parameter before the default op=new parameter to overwrite it during CalculiX analysis and have a step with op=mod active.
  • bug fixes (material unit converions)

To use the op=mod parameter, one must insert op=mod before op=new in the Keyword editor:

Download: Downloads – PrePoMax


I considered adding support for the op parameter in the Step controls editor. In CalculiX, the step controls are meant to set the solver parameters during incrementation. So they have a special purpose. But in PrePoMax, I could add an additional control parameter called Op, which would have entries as Boundary, Cload, Dload, Temperature … and the possibility to switch from the default “new” value to a “mod” value.

The problem I see is that these op settings would not be visible in the FE Model tree. The user could easily forget about them.

What do you think?

I am still looking for an example where the op=new settings cannot perform the required task…

Would be nice to have an option to change this somewhere without having to edit the keywords manually. Maybe when editing a load/BC ?

Like this ? Wrong results in a multistep analysis with shells and *BOUNDARY, OP=NEW · Issue #13 · Dhondtguido/CalculiX · GitHub

Perhaps support for *CONTROLS should come with a warning like in Abaqus:


We’ve seen too many cases of misuse of this keyword.

I don’t think this would be the best place. Imagine having a concentrated load and a surface traction load in the same step. If the op parameter is changed to op=mod for the concentrated force, it is automatically changed for all other *Cload keywords, as is surface traction internally (at least that is how I understand it). So, I considered adding this setting to a step instead of to the load.

I went through topics on this forum, but I still feel that op=new is more powerful and can do everything the op=mod can do. While the op=mod cannot do everything the op=new can do - like disable a load. So if I add it, I would like to keep its setting hidden somewhere deep - not to the Step editor. That is why I was thinking about Controls editor.

I can add a warning like this copied from the Calculix manual to when opening the Controls editor.

I was thinking that the other loads/BCs of the same kind could automatically adapt to the new setting but it’s not a perfect solution either. The step controls editor might be a good place because this setting wouldn’t be changed so often. In the future, BC/load manager could be the best location.

1 Like