richarda@cec825.atl.hp.com (06/18/91)
In article <91-06-016@comp.compilers>, bill@hcx2.SSD.CSD.HARRIS.COM writes: >As far as I know, there is only _one_ kind of mathematics. The FORTRAN >standard is referring to real mathematics, not any particular means of >approximating mathematics. Dealing with error values (such as INF, divzero, etc.) does not necessarily preclude one from "mathematicality." I seem to recall that the folks working on dataflow architectures rigorously defined the math for propogating error values so that traps, etc., would not be necessary. I don't recall the author but I believe the title of the paper was Error Values in Val. -- Send compilers articles to compilers@iecc.cambridge.ma.us or {ima | spdcc | world}!iecc!compilers. Meta-mail to compilers-request.
presberg@compass.com (David Presberg) (06/19/91)
In article <91-06-024@comp.compilers> richarda@cec825.atl.hp.com writes: > ... I seem to recall that the folks working on dataflow architectures > rigorously defined the math for propogating error values so that traps, > etc., would not be necessary. I don't recall the author but I believe the > title of the paper was Error Values in Val. Try "VAL -- A Value-Oriented Algorithmic Language: Preliminary Reference Manual", William B. Ackerman, Jack B. Dennis, MIT/LCS/TR 218, June 13, 1979. There are probably more recent articles or tech. reports on the language. Careful attention is given to the behavior of all forms of computational (e.g., "undef" operands of an operator, "miss_elt" -- missing component -- of an array object), and arithmetic errors (e.g., there are 20 rules for errors in integer operations alone, more for reals). - Pres David L. Presberg, Compass, Inc. Domain: presberg@compass.com .5&.5: compass!presberg@think.com uucp: {think,bu.edu,cvbnet}!compass!presberg Nicname: Pres -- Send compilers articles to compilers@iecc.cambridge.ma.us or {ima | spdcc | world}!iecc!compilers. Meta-mail to compilers-request.