Abstract: A method and apparatus for storing memory modeling data (20) in computer memory (76). The memory modeling data (20) is converted into an X-data value (36) according to a first mapping scheme (32). The first mapping scheme (32) associates the value of each digit of the memory modeling data (20) with a predetermined digit which has one of three values. The X-data value (36) is partitioned into subgroups (52). A character is mapped to each of the subgroups (52) according to a second mapping scheme (64). The mapped characters (60) are stored in computer memory (76).