Composer Iannis Xenakis (1922-2001), in his book Formalized Music (1963), includes a piece of Fortran IV computer code which produces a composition of stochastically generated music. This early example of indeterminate music made by a computer was in fulfillment of his goal of creating a musical composition of minimum constraints by letting the computer stochastically generate parameters. Stochasticity is used on all levels of the composition, macro (note density and length of movements) and micro (length of notes and pitches). This paper carefully analyzes the output composition and the variations the program might produce. Efforts are then made to convert these compositions into MIDI format in order to promote their preservation and increase their accessibility. The preservation of the Free Stochastic Music Program is beneficial to understand one of the first examples of indeterminate computer music, with similar techniques being found in modern day music creation software.
