The reliability functions of the general source with fixed-length coding

The reliability function problems with fixed-length source coding for the general source are studied for all rates R. Our fundamental philosophy in doing so is to convert all of the reliability function problems to the pertinent computation problems in the large derivation-probability theory. It turns out that this kind of new methodology, which was previously developed by Han (see ibid., vol.43, p.1145-64, 1997), enables us to establish quite compact general formulas of the reliability function for general sources including all nonstationary and/or nonergodic sources with countably infinite alphabet. Such general formulas are presented from the information-spectrum point of view.