Dialogue in REDUCE: experience and development

Abstract

The communication between a user @nd Q computer can be realized in the dialogue or package mode. In numer ical calculations the package mode is quite acceptable, but it is not so good for analytic calcul ations because of their specific char acter. In analytic cal cul a-tions an active search for solution i s, as a r ul e, done which is based, to a large extent , on the tr ial .-and-err or method. Al 1 moder n systems of analytic calculations use the dialogue mode. When organizing a dial ague, psychological factor s must, natu-r ally, be taken into account. 'T'he neglect of these factors decreases the efficiency in the use of the system. When devel oping the dialogue mode of the REDUCE system we did our best to include the r esults of the psy-chologic exper iment /I/. Among the universal systems the REDUCE system of computer al gebra /2/ is the most popular. The system is equipped with sufficiently powerful mathematics incl uciing, along with the polynomial algebr a, the oper ations on matr ices, differ entiation, integr ation, algebra of Dir ac r matr ices,etc. The po-pul ar ity of the system is expl aineci, large1 y, by the convenient ALGOL-like language which possesses all the necessary constructions fr om the standpoint of moder n sty1 e of pr og-r amming. 2. Dialogue mode in the REDUCE system. The dialogue mode of the REDUCE system is based on a special method of processing Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specfic permission. error s. For example, if an err or is revealed in the package mode the pr ogr am execution is inter r upted for the syntactic parsing of the remaining text. In the dialogue mode, the program execution is inter r upted, if an err or occur es, but, as opposed to the package mode, the control is tr ansfer red to a user. The expression r eponsible for an er r-Or is neglected in both the cases. In the dialogue mode a user …