Ramper

class fridom.framework.modules.Ramper(start_time: float, ramp_period: float, update_parameters: Callable[[fr.ModelState, float], None] = <function Ramper.<lambda>>, ramp_function: Literal['exponential', 'power_3', 'cosine', 'linear'] | Callable[[float], float] = 'exponential')

Bases: Module

A module for ramping up and down parameters during a simulation.

Parameters

start_timefloat

The time at which the ramping should start.

ramp_periodfloat

The period over which the ramping should occur.

update_parametersCallable[[fr.ModelState, float], None], optional

A method that updates the model parameters based on the ramped value. It should take the model state and the ramped value which is between 0 and 1.

ramp_functionstr or Callable[[float], float], optional

The ramp function. It can be one of the following strings: “exponential”, “power_3”, “cosine”, “linear” or a custom callable. The default is “exponential”.

Description

This module contains a list of ramp functions that can be used to ramp up and down parameters during a simulation. This can be useful for adiabatic processes or for slowly changing parameters. For example to ramp up the nonlinear term.

__init__(start_time: float, ramp_period: float, update_parameters: Callable[[fr.ModelState, float], None] = <function Ramper.<lambda>>, ramp_function: Literal['exponential', 'power_3', 'cosine', 'linear'] | Callable[[float], float] = 'exponential') → None

Methods

__init__(start_time, ramp_period[, ...])
cosine_ramp_func(theta)	Cosine ramp function.
disable()	Disable the module.
enable()	Enable the module.
exponential_ramp_func(theta)	Exponential ramp function.
is_enabled()	Whether the module is enabled or not.
linear_ramp_func(theta)	Linear ramp function.
power_3_ramp_func(theta)	Power 3 ramp function.
reset()	Stop and start the module.
setup(mset[, setup_mode])	Set the module up.
start()	Start the module.
stop()	Stop the module.
update(mz)	Update the model state.

Attributes

diff_module	The differentiation module to be used by this module.
grid	The grid of the model settings.
info	Return a dictionary with information about the time stepper.
interp_module	The interpolation module to be used by this module.
is_setup	Whether the module is set up.
mset	The model settings.
name
ramp_function	The ramp function.
required_halo	The required halo points for this module.

name = 'Ramper'

update(mz: ModelState) → ModelState

Update the model state.

Description

This method is called by the model at each time step. Child classes should overwrite this method to update the module. Make sure to decorate the method with the @module_method decorator.

Parameters

mzfr.ModelState

The model state at the current time step.

Returns

fr.ModelState

The updated model state.

static exponential_ramp_func(theta: float) → float

Exponential ramp function.

\[f(\theta) = \frac{e^{-\frac{1}{\theta}}} {e^{-\frac{1}{\theta}} + e^{-\frac{1}{1-\theta}}}\]

static power_3_ramp_func(theta: float) → float

Power 3 ramp function.

\[f(\theta) = \frac{\theta^3}{\theta^3 + (1 - \theta)^3}\]

static cosine_ramp_func(theta: float) → float

Cosine ramp function.

\[f(\theta) = \frac{1}{2} \left(1 - \cos(\pi \theta)\right)\]

static linear_ramp_func(theta: float) → float

Linear ramp function.

\[f(\theta) = \theta\]

property info: dict[str, str]

Return a dictionary with information about the time stepper.

Description

This method should be overridden by the child class to return a dictionary with information about the time stepper. This information is used to print the time stepper in the __repr__ method.

property ramp_function: Callable[[float], float]

The ramp function.

Parameters

thetafloat

The scaled time value (between 0 and 1).

Returns

float

The ramped value (between 0 and 1).