This code accompanies the paper A Primer on Variational Laplace by Peter Zeidman, Karl Friston and Thomas Parr. https://doi.org/10.31219/osf.io/28vwh

A standalone implementation of the algorithm for MATLAB or Octave can be found in /matlab/toolbox/variational_laplace.m . Note that the example code in /matlab/examples/ compares the output of the standalone implementation against that of the SPM toolbox, so SPM needs to be on the MATLAB path for the example code to run to completion.

Instructions:

1. Download the matlab/ folder to somewhere convenient on your computer
2. Using MATLAB or Octave, change the working directory to the matlab/examples/ folder
3. Run the script run_VL_all.m to reproduce the figures in the paper

The Attention to Visual Motion example requires Dynamic Causal Modelling (DCM) for fMRI, implemented in the SPM software package. To run this example:

1. Download and install the SPM toolbox.
2. Download and run the MATLAB script from the bottom of the SPM data set webpage. This will download the data and run the analysis.