Start here

After you install and load up the package in MATLAB (check Installation if you havent), you can start using the Mapper algorithm by running the following command:

opts = BDLMapperOpts(32, 20, 70);
res = mapper(data, opts);

  • This will set up a default Mapper algorithm with 20 bins, 70% overlap, and using a k-value of 32.

  • The data parameter should be a matrix of size n x m where n is the number of samples and m is the number of features. The Mapper will dimensionaly reduce on the rows dimension, compressing the data into a graph structure that represents the shape of the data.

The res variable will contain the Mapper output, representing the graph structure of the data. You can simply visualize it as follows:

figure;
g = graph(res.adjacencyMat);
plot(g, 'Layout', 'force', 'Usegravity', true, 'WeightEffect', 'inverse');

Next steps

For more information on the Mapper algorithm, check the Run Mapper as a library page.

Or you can follow the tutorials to get a step-by-step guide on how to use the Mapper algorithm in different scenarios. Tutorial 1: Running Mapper as a Library is a good place to start.