`resistor`

Module: devtests.bidomain.resistor.run

Section author: Gernot Plank <gernot.plank@medunigraz.at>

Validation of physical units used in extracellular voltage and current stimulation code

Problem Setup

This test generates a simle slab geometry of length $L=10 mm$ with a square cross section of edge length $a = 0.1 mm$ . A conductivity of $1 S/m$ is assigned. The total resistance between the two terminals of size $a imes a$ is then $1 \mu S$ . To use the extracellular space of the bidoman model as an approximation of a resistor, a PASSIVE ionic model is used. As we aim to prevent current entering an intracellular path we minimize current flow into the intracellular space by increasing the membrane resistance and decreasing the conductivity of the intracellular current path.

Two tests are performed. In both tests, the right hand side terminal will be grounded. Into the left hand side terminal we either inject current of a total strength of $1 \mu A$ or we impose a voltage of $V_{x=-L/2} = 1000 mV$ . As we model a resistor in both cases the total voltage drop across the resisor has to be $1000 mV$ and the total current flowing over the resistor has to be $1 \mu A$ . The setup is illustrated below:

Usage

This example specifies only one argument, --stimulus, which can be set to extra_V or extra_I.

./run.py --stimulus extra_I

Tests

extra_V

Tags: FAST SERIAL

Checks:

Compare against stored reference: max_error(phie.igb.gz)
Compare against stored reference: max_error(vm.igb.gz)

Last run: 2023-12-06 01:04:44.888789, revision {‘base’: ‘f172baea’}, dependency revisions {PT_C: 31642c1e,cvsys: 69164767,eikonal: 5fbbfda3,elasticity: edfdcbb3}

Runtime: 0:00:00.751701
ALL PASSED
  PASS max_error(phie.igb.gz): 6.103515625e-05
  PASS max_error(vm.igb.gz): 6.103515625e-05

extra_I

Tags: FAST SERIAL

Checks:

Compare against stored reference: max_error(phie.igb.gz)
Compare against stored reference: max_error(vm.igb.gz)

Last run: 2023-12-06 01:04:45.686295, revision {‘base’: ‘f172baea’}, dependency revisions {PT_C: 31642c1e,cvsys: 69164767,eikonal: 5fbbfda3,elasticity: edfdcbb3}

Runtime: 0:00:00.752641
ALL PASSED
  PASS max_error(phie.igb.gz): 6.103515625e-05
  PASS max_error(vm.igb.gz): 6.103515625e-05