Is it possible to define a region with variables?

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1

Hi all,

I want to be able to calculate the appropriate simulation dimensions, based on the lattice orientation and empirical thresholds for accurate simulation. I would like to be able to include a template set-up based on the lattice orientations and the lattice constant as the only inputs, and to define regions with variables based on the outputs.

However, I cannot seem to be able to define a region with variables, as, for example:

variable a equal 10
region cube block 0 v_a 0 v_a 0 v_a
create_box 1 cube

I would get the following error:

ERROR on proc 4: Box bounds are invalid (domain.cpp:140)
ERROR on proc 1: Box bounds are invalid (domain.cpp:140)
ERROR on proc 2: Box bounds are invalid (domain.cpp:140)
ERROR on proc 3: Box bounds are invalid (domain.cpp:140)
ERROR on proc 0: Box bounds are invalid (domain.cpp:140)

AND in the logfile, it reads: “Created orthogonal box = (0 0 0) to (0 0 0)”

Clearly, there is an error when trying to read variables with the syntax I am applying when defining a region. Is it possible to define a region with variables, and if not, could this be a future fix?

With regards,

2

variable a equal 10
region cube block 0 v_a 0 v_a 0 v_a
create_box 1 cube

Use the $-syntax:
region cube block 0 $a 0 $a 0 $a

3

I had done that, but I now realise that the issue was one of my initially defined variables was not actually defined (oops).

Thanks for the reply/ validation!
Nathaniel