[Bug] Parameters with scalar field written as vector field

[lang-m]

Some of the energy terms (e.g. ZhangLi.u) can be defined with a scalar (dim=1) field. However, when writing the input for OOMMF the field is saved with extend_scalar=True (which repeats the single component three times). For ZhangLi.u OOMMF fails because it expects a scalar field but reads a vector field.

The relevant parts of the code:

oommfc/oommfc/scripts/evolver.py

Lines 24 to 25 in 547ece4

	if hasattr(evolver, "u"):
	umif, uname = oc.scripts.setup_scalar_parameter(evolver.u, "zl_u")

oommfc/oommfc/scripts/util.py

Lines 78 to 80 in 547ece4

	def setup_scalar_parameter(parameter, name):
	if isinstance(parameter, df.Field):
	parameter.write(f"{name}.ovf", extend_scalar=True)

@marijanbeg Is there any casy where we need extend_scalar=True in the input for OOMMF (because we start from a scalar field where OOMMF expects a vector field)?