Unit checking in EPhys parameters

[lkoelman]

Hi there,

It would be great if unit checking could be added to Ephys parameters when they are instantiated. This would be pretty easy to implement. Units of Hoc variables can be queried using h.units() (if they are defined), and Python has some great unit checking/conversion packages. I have hacked together some code that may be a good start:

import re
import pint # popular units package
from neuron import h
ureg = pint.UnitRegistry()

nrn_units = h.units(hoc_varname)
units_nodash = nrn_units.replace('-', '*') # some NEURON units are defined with dashes
units_exponents = re.sub(r'([a-zA-Z]+)(\d)',r'\1^\2', units_nodash) # adds '^' char for exponents
target_units = ureg(units_exponents)

param_quantity = ureg.Quantity(param_value, param_units_str)
try:
    converted_quantity = param_quantity.to(target_units)
except pint.errors.DimensionalityError:
    raise ValueError('incompatible units')

setattr(nrn_obj, hoc_varname, converted_quantity.magnitude)

Would something like this be possible?

Cheers,
Lucas.

[wvangeit]

Sorry for the very late reply, I lost track of this issue.
Yes, it's a good idea, but in the short term I'm afraid we won't have time to implement this from our side, but please feel free to contribute code.