The Museum of HP Calculators

HP Forum Archive 14

 Calculator Logic Systems, Part IaMessage #1 Posted by bill platt (les Estats Unis d'Amerique) on 11 June 2004, 2:22 p.m. OK, To start out, I am merely posting an outline as I see it, of calculator logic systems as currently in use. This is "Part Ia" because of my previous post: The idea here is that I will first post this, so everyone can see it, and then in a few days I will post my "treatise" as it were. Please post any glaringly obvious omissions, and i wil ledit this list (within my prerogative, of course) so that we have a nice "seminar outline" as it were....is this getting to be too academic; oh well! Note that I am trying to stay away from the more advanced and specialized features---this icludes PMT IRR etc on financials, Statistics, unit conversions etc on scientifics etc. Best regards, Bill Platt Calculator Operating Systems: (Leaving out matrices and other special or utility functions eg conversions, units etc) Group 1: Stack Based RPN (postfix except for register work which is infix) programming is essentially machine code level RPL (postfix everything) programming is essentially high-level (except assembler hacking!) Variations: stack depth variable handling data types exponentiation direction of entry compex number handling register handling register arithmetic programming features statistics/special features handling "Adding Machine" (in between group 1 and 2) postfix for addition and subtraction; infix for multiplication and division Group 2 (also known as "Direct Calculation" as opposed to "Formula Entry") "Algebraic with precedence" with postfix "1 number functions" "Algebraic" without precedence (and postfix "1-number functions") Ordinary 4-function infix arithmetic, postfix "1-number" functions) Variations on algebraic: "history" stack "last" (sometimes called "ANS") "swap" "input" for "2-number functions" and other special features (e.g. statistics) handling/display of intermediate results chain computation computation with a constant complex arithmetic Note that these variations are by no means universal. The meaning of "swap" "k" et cetera may differ greatly from one maker to another or even from one model to another. Numerous variations exist on the handling of: clearing & cancelling m^n (y^x, x^y, x_Root-of_y etc) % statistics permutation & combination variables and or registers or memories register/memory arithmetic programming rules use of parenthesis in non-precedence machines Group 3: Formula Based "Formula Entry" (infix everything except usually x^2 is usually postfix and y^x is infix) "Formula Entry" with "implicit multiplication" (again infix everything except x^2) Variations on Formula Entry (Sometimes called "direct algebraic logic," "visually perfect algebraic logic" etc). history stack scrollable edit intermediate results use of previous results ("ANS") Edited: 11 June 2004, 2:25 p.m.

 Re: Calculator Logic Systems, Part IaMessage #2 Posted by Veli-Pekka Nousiainen on 11 June 2004, 7:35 p.m.,in response to message #1 by bill platt (les Estats Unis d'Amerique) Bill Platt wrote: RPN (postfix except for register work which is infix) programming is essentially machine code level ======================================== VPN> SF__, XEQ_, etc... is prefix stuff ======================================== RPL (postfix everything) programming is essentially high-level (except assembler hacking!) ========================================= VPN> SysRPL has on-stream commands, etc. VPN> 'Algebraics+are+infix' ========================================= X Variations on Formula Entry (Sometimes called "direct algebraic logic," "visually perfect algebraic logic" etc). X ....but where does the HP-71B CALC mode belong to? [V <)P <)N]

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