Advanced tips and tricks

A lot of advanced tips and tricks like keeping track of IDs and using loops have already been covered in the example. This section serves as a quick reference guide where the most important features are listed again - for their application please refer to the example above.

Get the ID of the last volume:

Id("Volume")

• Loop for a certain number of times:

#{Loop(10)}
    ...
#{EndLoop}

If-statemet:

#{If(uu>=7)}
    ...
#{EndIf}

Get surfaces of a certain volume (range):

surface in volume {ID}

Selection based on geometry:

with z_coord={z_val}
with x_max>={x_val}
with y_min<{y_val}

General selection of volumes (and surfaces etc.):

all
except
and

Use Python inside of Cubit

You can also use python inside cubit for scripting. Just activate the script-tab under Tools -> Options -> Layout -> Show Python Tab

Now you can use python inside cubit:

cubit.cmd("reset")
xList = [1,2,3,4,5]
for x in xList:
  cubit.cmd(f"brick x {x} y {x} z {x}")
  cubit.cmd(f"move volume {x} x {x}")
cubit.cmd(f"unite volume all except 1")
cubit.cmd(f"subtract volume 1 from 2")

Use Cubit inside of Python-Editor

You can also use your favourite Code-Editor (like VSCode) but here you need to import and initialize the cubit library first:

import sys 
#path to cubit binary
sys.path.append("/path/to/Coreform-Cubit-2020.2/bin")
import cubit
#Without this init-command, i get an segfault
cubit.init(["cubit","-nojournal"])

Please note that the cubit.init("cubit") is critically, otherwise you can get a segfault.

Export degenerate elements

Since blocks can only contain one type of element, the only option to export multiple element types in one block is to write them as a degenarte version of the "main" element type - if possible (e.g. write a wedge as a hex element). Attention: This feature is not activated by default, hence exporting a block with multiple element types will result in holes! If you have strange problems with your simulation, check if this might be the cause! To activate this feature just use

Set Block Mixed Element Output Degenerate

somewhere before you export the mesh.