The project is a Prevas (http://www.prevas.se) LabVIEW port of Sebastian Madgwick C# Ahrs Library. https://decibel.ni.com/content/people/rois?view=documents

There is a youtube video showing this filter in action: http://www.youtube.com/watch?v=-uKoqIaFCpU

See Sebastian's company page at: http://www.x-io.co.uk/

There is also a data value reference circular buffer implementation. https://decibel.ni.com/content/docs/DOC-20403