cubie.systemmodels.systems.decays

Exponential decay ODE system for testing.

This module provides a simple ODE system where each state variable decays exponentially at a rate proportional to its position.

Classes

Decays([precision])

Exponential decay system for testing purposes.

class cubie.systemmodels.systems.decays.Decays(precision=<class 'numpy.float64'>, **kwargs)[source]

Bases: GenericODE

Exponential decay system for testing purposes.

A system where each state variable decays exponentially at a rate proportional to its position. Observables are the same as state variables * parameters (coefficients) + index.

Parameters:

precision (numpy.dtype, optional) – Data type for calculations, by default np.float64.
**kwargs (dict) – Must contain ‘coefficients’ key with list of decay coefficients.

Notes

If coefficients = [c1, c2, c3], then the system will have three state variables x0, x1, x2, and:

dx[0] = -x[0]/1, dx[1] = x[1]/2, dx[2] = x[2]/3

obs[0] = dx[0]*c1 + 1 + step_count, obs[1] = dx[1]*c2 + 2 + step_count, obs[2] = dx[2]*c3 + 3 + step_count.

Really just exists for testing.

__init__(precision=<class 'numpy.float64'>, **kwargs)[source]

Initialize the decay system.

Parameters:

precision (numpy.dtype, optional) – Data type for calculations, by default np.float64.
**kwargs (dict) – Must contain ‘coefficients’ key with list of decay coefficients.

build()[source]

Build the CUDA device function for the decay system.

Returns:: Compiled CUDA device function implementing the decay dynamics.
Return type:: function

correct_answer_python(states, parameters, drivers)[source]

Python testing function.

Do it in python and compare results with CUDA implementation.

Parameters:

states (numpy.ndarray) – Current state values.
parameters (numpy.ndarray) – Parameter values.
drivers (numpy.ndarray) – Driver values.

Returns:

A tuple containing (dxdt, observables) arrays.

Return type:

tuple of numpy.ndarray