# Active Inference Code written to understand Karl Friston on Active Inference ## Programs based on [Parr, Pezzulo, Friston 2022 Textbook](https://direct.mit.edu/books/oa-monograph/5299/Active-InferenceThe-Free-Energy-Principle-in-Mind) File|Description -------------------|--------------------------------------------------------------------------------------------------- hmm_7_2.py|HMM Example from Section 7-2 ## Programs based on [Life as we Know it](https://royalsocietypublishing.org/doi/10.1098/rsif.2013.0475) File|Description -------------------|--------------------------------------------------------------------------------------------------- ai.bib|Bibliography ai.tex|Derivations of equations selforg.py|Replication of Figure 2, Self Organization and the emergence of macroscopic behaviour, from Friston & Ao, [Free Energy, Value, and Attractor](https://www.hindawi.com/journals/cmmm/2012/937860/) huygens.py|Test for Huyghens oscillator in selforg.py ## Programs based on [A Step-by-Step Tutorial on Active Inference and its Application to Empirical Data](https://www.researchgate.net/publication/348153427_A_Step-by-Step_Tutorial_on_Active_Inference_and_its_Application_to_Empirical_Data) File|Description -------------------|--------------------------------------------------------------------------------------------------- example2.py|Example 2 exercise2.py|Exercise 2 figure2.py|Figure 2 message_passing.py|Ported from [Message_passing_example.m](https://github.com/rssmith33/Active-Inference-Tutorial-Scripts/blob/main/Message_passing_example.m) pomdp.py|POMDP example and library for solvers pomdp_driver.py|POMDP example ## Programs based on [A tutorial on the free-energy framework for modelling perception and learning, by Rafal Bogacz](https://www.sciencedirect.com/science/article/pii/S0022249615000759) File | Remarks | ---------------|------------------------------------------------------------------------------------------- feex1.py| Exercise 1--posterior probabilities feex2.py| Exercise 2--most likely size feex3.py| Exercise 3--neural implementation feex5.py| Exercise 5--learn variance ## ODE solvers File | Remarks | ---------------|------------------------------------------------------------------------------------------- euler.py|Euler's method rk4.py|Workhorse Runge-Kutta 4th order sde.py|Euler-Maruyama method ## pydmp demos File | Remarks | --------------------|------------------------------------------------------------------------------------------- pymdp_demo1.py|[Conor Heins et al--pymdp: A Python library for active inference in discrete state spaces](https://arxiv.org/abs/2201.03904) tutorial1.py|[Active inference from scratch](https://pymdp-rtd.readthedocs.io/en/latest/notebooks/active_inference_from_scratch.html) tutorial2.py|[The Agent API](https://pymdp-rtd.readthedocs.io/en/latest/notebooks/using_the_agent_class.html) tutorial_common.py|Common code for tutorials ## Miscellaneous File | Remarks | ---------------|------------------------------------------------------------------------------------------- ai.wpr|Project for Python Code template.py|Template for creating additional programs