Mineral and raw materials complex (MRC) belongs to the class of large economic systems. Construction of models, statement of planning and management tasks for such systems are connected with overcoming of considerable complexities of theoretical and practical character.

Creation of the system of state cadastres of mineral deposits and, including the economic cadastre of industrial deposits of non-ferrous metals requires the formation of a powerful information base.

The development of advanced information support is one of the most important problems arising in the creation of automated control systems (ACS). The need to organize extremely large arrays of diverse information and to access them efficiently (recording, reading, information retrieval, processing) requires the inclusion in the ACS of a complex and multifunctional information retrieval system (IRS).

The problem of optimal coding of information texts largely determines the efficiency of information retrieval systems (IRS) and automatic control systems (ACS). The solution of this problem leads to minimizing the required computer memory capacity and increasing the speed of information retrieval.