A Programming Language /1500 (APL /1500),

Abstract : The document describes the implementation of APL (A Programming Language) for the IBM 1500 Instructional System. It is a revision of the original User's Guide supplied with the first release of the APL System for the 1500. The revised document incorporates a number of extensions to the implementation of APL, particularly the inclusion of the light pen and file handling capabilities. The file items are variable-length, index sequential, randomly accessable and can be any arbitrary APL array (characters or numbers as a scalar, vector or matrix). The full APL is implemented on the 1500 system with only minor restrictions, primarily relating to the smaller size of the workspace as compared to the IBM 360 implementation. Extensions, in addition to the files, include operation of the special terminal hardware of the 1500, primarily the CRT and the film image projector. (Author)