Scratchpad was a computer algebra system developed at IBM in the early 1970s. Like M&M (Maple and Mathematical) and other systems today, Scratchpad had one principal representation for mathematical formulae based on "expression trees". Its user interface design was based on a pattern-matching paradigm with infinite rewriterule semantics, providing what we believe to be the most natural paradigm for interactive symbolic problem solving. Like M&M, however, user programs were interpreted, often resulting in poor performance relative to similar facilities coded in standard programming languages such as FORTRAN and C. Scratchpad development stopped in 1976 giving way to a new system design that evolved into AXIOM. AXIOM has a strongly-typed programming language for building a library of parameterized types and algorithms, and a type-inferencing interpreter that accesses the library and can build any of an infinite number of types for interactive use. From: How to Make Axiom into a ScratchPad", Jenks and Trager, 1994. |