Pithoprakta is stochastic work. Stochastic processes have a random probability distribution that cannot be predicted. Examples include bacterial growth patterns, electrical current fluctuation, and the movement of particles within a fluid. Pithoprakta was composed for 49 musicians – 2 trombones, xylophone/woodblock, and 46 strings. Each instrument is conceived as an independent molecule according to the Maxwell-Boltzmann distribution law. This law describes the probable velocity ranges of particles moving within an idealised gas at thermodynamic equilibrium. The ranges differ based on the temperature and pressure of the gas. In Pithoprakta, Iannis Xenakis divides the work into sections and calculates the velocity ranges of 1148 particles. The vertical axis represents the speed of the particle; the horizontal axis represents time. The musical notation maps the particle velocities to frequencies. Each vertical square represents a major third and every five horizontal squares represent one measure. The lines drawn between the plot points are represented by the instruments playing glissandi between the indicated frequencies.