This GNU Octave function identifies the stress cycles in an irregular time series of stress. The rainflow algorithm code has been prepared according to the ASTM standard "Standard practices for cycle counting in fatigue analysis" and is optimized considering the calculation time.

This is the same algorithm as that described by de Jonge, J.B.(1982): "The analysis of load-time histories by means of counting methods". The results are exactly equal to those obtained by the algorithm described by Matsuiski, M. and Endo, T. (1969): "Fatigue of metals subjected to varying stress".

The code was originally developed for Matlab by Dr. Adam Nieslony.

A package suitable for GNU Octave is provided here - complete with references and instructions for compilation, installation and testing.