Struct FrankenhaeUserHuxleyAxon 

pub struct FrankenhaeUserHuxleyAxon {

    pub v: f64,
    pub m: f64,
    pub h: f64,
    pub n: f64,
    pub p: f64,
    pub c_m: f64,
    pub p_na: f64,
    pub p_k: f64,
    pub p_p: f64,
    pub g_l: f64,
    pub e_l: f64,
    pub na_ratio: f64,
    pub k_ratio: f64,
    pub v_t: f64,
    pub dt: f64,
    pub sub_steps: usize,
    pub gain: f64,
}

Frankenhaeuser-Huxley 1964 — myelinated nerve fibre model.

Extension of HH for myelinated axons (Xenopus node of Ranvier). Uses Goldman-Hodgkin-Katz (GHK) permeability-based current equations with 4 gating variables: m (Na activation), h (Na inactivation), n (delayed rectifier K), p (slow non-specific current).

GHK current for monovalent ion: I = P * F²V/(RT) * (C_i - C_o * exp(-FV/RT)) / (1 - exp(-FV/RT))

Simplified (FH convention, V relative to rest, temperature factor absorbed): I_Na = P_Na * m² * h * ghk_drive(V, Na_i/Na_o) I_K = P_K * n² * ghk_drive(V, K_i/K_o) I_p = P_p * p² * ghk_drive(V, Na_i/Na_o) [non-specific, Na-like] I_L = g_L * (V - E_L)

C dV/dt = -(I_Na + I_K + I_p + I_L) + I_ext

The GHK driving force is the key distinction from conductance-based HH — it is nonlinear in V and depends on concentration ratios.

Frankenhaeuser & Huxley, J Physiol 171:302, 1964. Frankenhaeuser, J Physiol 160:46, 1962 (rate constants).

Fields

v: f64

m: f64

h: f64

n: f64

p: f64

c_m: f64

p_na: f64

p_k: f64

p_p: f64

g_l: f64

e_l: f64

na_ratio: f64

k_ratio: f64

v_t: f64

dt: f64

sub_steps: usize

gain: f64

Implementations

impl FrankenhaeUserHuxleyAxon

pub fn new() -> Self

fn ghk_current(v: f64, c_ratio: f64, v_t: f64) -> f64

GHK current for monovalent ion (FH convention).

Returns current density contribution in mA/cm² when P is in FH-scaled units (absorbs F*[C_o]*1e-3 into P).

I = P_eff * gates * V/V_T * (r - exp(-V/V_T)) / (1 - exp(-V/V_T))

where r = [ion]_i / [ion]_o, V_T = RT/F. At V→0: uses L’Hôpital limit = P_eff * (r - 1).

The Faraday scaling: P_eff = P_raw * F * [C]_o / 1000 is absorbed into the permeability constant (FH Table 4 values are already in these effective units: mA/cm² at unit gating).

pub fn step(&mut self, current: f64) -> i32

pub fn reset(&mut self)

Trait Implementations

impl Clone for FrankenhaeUserHuxleyAxon

fn clone(&self) -> FrankenhaeUserHuxleyAxon

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FrankenhaeUserHuxleyAxon

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FrankenhaeUserHuxleyAxon

fn default() -> Self

Returns the “default value” for a type.