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Talk:Counter machine

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1332:, and with spaghetti-code everything can be done. The article should not list lengthy example programs, but give only the code to calculate the predecessor function without using DEC(r), which is short and interesting. Maybe also the code to copy one variable to another without using CPY(m,n). And leave it there. The different models should be given in tabular form, with reference to the literature where found (this information is now in the 'Counter-machine model' article, but not nice and uniform, and very sloppy). Remove also the 416: 406: 388: 2071:" . Kleene's point seems to be that the primitive recursive functions are all elementary and vice versa ... except this: "From this it follows that there are non-elementary primitive recursive predicates..." (p. 272). Kleene refers us back to §55 where he observes: "Ackermann's investigation shows that ℰ(a) grows faster with increasing a than any primitive recursive function of a (just as 2 grows faster than any polynomial in a)...." (cf p. 272). 144: 2090:}. He develops the notions of "computable functions" from this model. Then he develops all the stuff he needs to simulate the "elementary functions" e.g. the "bounded sum Σ" and "bounded product Π", etc. and then he proves that the number 2 is not elementary (at least I think that's what he's doing, am confused here by the weird symbolism, it could be Ackermann's function, or just 2 ... cf "Lemma" on page 59.) 71: 53: 1414:
the unary number in the register is ODD or EVEN, and at the same time it counts UP a second register B to EVEN(N/2). Then depending on the ODD-EVEN outcome it either moves 3*EVEN(N/2)+2 or EVEN*(N/2) back into register A. (Thereby doing the { (3*N+1)/2, N/2 } form of Collatz). But... a few months ago I ran into (via a bibliography of a Blass-Gurevich paper) a paper by Rich Schroeppel 1972,
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to go take a peek. The impossibility argument can be summarized in a sentence or two: A 2CM that halts must map certain arithmetic progressions in a linear fashion. This is incompatible with most interesting functions like 2^N. The paper spends many pages filling in the details. You might also check with Frances Yao (nee Chu) who discovered the result at the same time as I did.
22: 1560: 2063:, but remarks that then * and are redundant." (p. 526). Kleene refers us back to his section §57 where he is developing the μ-operator (the unbounded version). In §57 there's an extended example I. "A function is "elementary", if it can be expressed explicitly in terms of variable natural numbers, the constant 1, the functions +, * and and the operations Σ 1838:
Here's a state-machine-like version with 11 instructions (not counting HALT) if you count the "output" instruction that appears at the start. I inserted it so I could see better what was going on. I use Excel to simulate these things. So this one uses this instruction set. "Test" is really just a NOP
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I don't know of a better multiplication algorithm. There hasn't been much work with counter machines, before or since my paper. There has been a fair amount of work on the 3N+1 problem; look up Jeff Lagarias, who does a review every few years. I didn't know the 1972 paper was on the net; I'll have
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Then, he discusses the class ℰ (script-E) i.e. "those number theoretic functions which can be defined from the initial functions: constant 0, successor S, projections (onto the ith coordinate), addition +, modified subtraction ∸, multiplication * and exponentiation 2, by applications of composition
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I ran into something important with regards to the inadequacies of a 2-counter Collatz counter-machine. As I noted above I've "built" in less than 16 instructions a two-counter machine that generates Collatz sequences given any starting number. In register A it counts down N by twos to find whether
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Counter automata are a simpler kind of automata, but, while in theory similar structures (a finite state machine with one or more counters), the two have very different applications (counter automata in formal language theory, while counter machines are a study of computer science computations) and
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Out of curiosity I've sketched an algorithm to do Collatz on the "tag machine" using an algorithm similar to the ones posted above for the counter machine (i.e. divide by two while calculating EVEN(N/2)). (I need to simulate it to check it.) It requires about the same number of instructions (on the
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Given all this, we can conclude that a 2-counter machine, while quite adequate for a single-instance Collatz sequence (i.e. given a starting N), is insufficient to handle all sorts of computations required for Godelization, given straight-up unary-numerical inputs (i.e. not encoded at the input and
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N, sqrt(N), Fib(N), Smallest_Prime_Factor(N), etc. He comes to the Collatz question but notes it is unsolved (his 2-counter algorithm seems to be the same as the one I'm using except it is doing {(6)*EVEN(N/2)+(4), N/2} ), i.e. the classical { 3*N+1, N/2 } version. There's a lot more. He notes that
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Did you ever ran into a "better" algorithm for your little challenge to write a multiply program for a 3CM? (I don't have one, but it sounds like a fun challenge. If I can figure your proof out, I may add a brief sketch of it to a wikipedia page titled "Proof of impossibility". Your observation
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A Corollary is that a 2-counter machine can compute any partial recursive function if its input is coded 2 and its output is encoded as 2 (I think this is in Minsky). He goes on to his major proof ("given N, a two-counter machine cannot compute 2") and then adds more corollaries: that no 2-counter
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Indirect addressing must be dealt with. Any instruction can be turned into an indirect, even an unconditional jump. Here S denotes "Source-"register and "D" denotes "Destination-"register, A denotes accumulator or any other special register, "i" (or "iD", "iS") denotes "indirect", "d"= NOT(i) (or
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Is this a good idea? Others have tried to do something like this on wikipedia for a computer "pseudocode" and failed. They gave it up. We will just end up in argument. Do the mnemonics really matter? For example, I usually use D ("Down") for "Decrement" and U ("Up") for "Increment". But I changed
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article should be merged into the 'Counter-machine' article, and deleted. To not overload the article one should remove the discussion of the Turing-equivalence, and just mention that counter machines can compute all computable functions . Which by the way is obvious, as counter machines allow
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I agree with your interpretation. But there are complications ... There's more I want to write about this but it got complicated and I ran out of time. I'll go away and draw something and think about this. (See the email I sent Schroeppel back on ~1 Aug and his response, below.)
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The following touches on my cryptic note and the 2 business. I don't understand it yet. In the back of Kleene 1952 p. 526 under the bibliographic reference for Laszlo Kalmar, is a note: "Kalmar takes, as his basis for elementary functions the variables, 1, +, *, |a-b|, ,
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indicates indirect addressing. But the "i" and "d" are pretty good because they act like parameters too. And they are Boolean (i.e. for example, perhaps "i"=1, "d"=0). I have simulated this on a spreadsheet recently -- all four parameters describe the functions nicely.
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page gives "counter machine" as a synonym, so there's no reason for two separate pages. (But maybe a "counter automaton" is a subset of "counter machine" with just one register? The page is unclear.) Moreover, "Counter automaton" is mostly a stub. Finally, the
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Bill, I hope this move of the material is satisfactory. You wrote "But there are complications ... There's more I want to write about this" — I'm interested in what those complications might be. BTW, using Minsky's 2CM from his book
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In a 2007 paper by Derschowitz and Gurevich I ran into a citation to your 1972 paper (that you wrote while at the MIT AI labs) called "A Two Counter Machine Cannot Calculate 2^N". I was then able to download it off the
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for a rather elaborate (unsurprisingly "obscure") coding that simulates the configuration of a UTM by means of a Gödel number, whose factorization is of form 235, in one of the registers. Although that might raise
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1 CLR(rY) 9 JZ (rW,13) 2 CLR(rW) 10 INC(rX) 3 JZ (rX,8) 11 DEC(rW) 4 INC(rY) 12 J (9) 5 INC(rW) 13 CONTINUE 6 DEC(rX) 7 J (3) 8 ??
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output as Goedel numbers). I'm sure this has a bearing on what you've reported, but I don't know quite what it is (and suspect I don't have the know-how to figure it out). Bill
834:"dD", "dS") denotes direct. We might have to use e.g. "c" or "k" or something for "immediate constant", where "func" is some 2-parameter function such as ADD or COPY or INC r: 246: 184: 1579:, 1967), I can get an 11-instruction Collatz program, but I think it's probably just the one you have, but placing goto info in the increment instruction (as Minsky did). -- 2306:: I'm convinced by your explanation that counter automata are for formal language theory while counter machines are for models of computation. I withdraw my merge support. 902:
The reason I have not used parenthesis is because the assemblers I have used for microcontrollers do not use them. But maybe parentheses are okay, like a function in EXCEL.
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Here's one version with instruction set { INC(r), DCR(r), jZ(A,addr); j(addr) } thus it assumes that instructions are executed in sequence unless a jump occurs.
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that tag machines are more powerful that what we need for a Collatz sequence (can a tag machine calculate 2 given N encoded as unary on its tape ??),
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I've replied to some of your questions about tag machines, including "can a tag machine calculate 2 given N encoded as unary on its tape??" at
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includes "the variables", the constants 0 and 1, addition +, "modified" (proper) subtraction ∸ and bounded sums and product. He defines as
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And by this he means 2*3*5*7, where a 4-counter machine made of counters W, X, Y, Z is simulated by the two-counter machine.
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Frances Yao independently proved the major theorem in April 1971, and he claims his proof was discovered in September 1970.
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Any counter machine can be simulated by a 2-counter machine, provided an obscure coding is accepted for the input and output.
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order of 20) as the counter machine. I would not be surprised to find out that it can be "morphed" into the tag-algorithm.
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about the Collatz Conjecture/Ulam problem really caught my eye; that problem is mentioned there too as an "open" problem).
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With the "referential library" (RefLib), the "referential model" can implement ALL other instruction sets from similar
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to expand the RefLib script templates into standard instructions. The scripts are for explaination and demonstration.
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The CONTINUE instruction is a "template instruction" for continuing into the context where the RefLib will be used.
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To fix a "standard style" (and reader "see the same as the same") for the algorithms and examples into the articles.
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related articles on Knowledge. If you would like to participate, please visit the project page, where you can join
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computer, they are common, as is CLR and CPY. Some folks use DCR for decrement. What is really important is to
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1 CPY(rX,r) 6 JZ(r0,3) 2 CPY(rY,rW) 7 JZ(rW,9) 3 JZ(r,7) 8 INC(r) 4 DEC(r) 9 CONTINUE 5 DEC(rW)
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Also, if I had a choice I would prefer to use the authors' original mnemonics, rather than a standard set.
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article with style (tables) and examples compatible with the recommendations fixed (to be consensus) here.
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models (ex. with stack or accumulator) may be fix, with simple changes, different "referential models".
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Here's my take on Schroeppel's paper: I see it primarily as showing that what he so readily accepts as
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A weaker but Collatz-capable machine (that cannot calculate 2 given N encoded as unary on its tape),
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The "referential library" is a sinple list of "new instructions" implementarions, they may be see as
2225: 1357: 2202:. I prefer to avoid detailed discussion of tag machines here (or of counter machines over there). -- 21: 1467:
that the argument and computed value of a function are just the numbers stored in certain registers
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Sorry, but the above is bogus. I am sticking with the convention in Boolos-Burgess-Jeffrey (2002)
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indicates direct addressing; k indicates immediate adddressing (constant derived from instruction)
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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strategy: each similar model with a different instruction set may be "emulated" by the RefLib.
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What does DEC(r) do if register r contains zero? This doesn't seem to be defined anywhere.
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I guess all that my cryptic comment was, was this (it was lost when my Excel froze): that it
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in more primitive terms (somehow) before you use them in the text. This is touched on in the
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i/o scheme, it may be able to compute some, but not necessarily all, recursive functions. --
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MIT A.I. Laboratory, Artifical Intelligence Memo #257. This is available on the web at
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Requested articles/Applied arts and sciences/Computer science, computing, and Internet
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counter machine can simulate a Turing machine, what he is really after here is that
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func( d, rs, d, rD) e.g. CPY (rS,rD), INC (d,r,d,r) = INC r; DEC (d,r,d,r)= DEC r
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I have not seen a stack in any models. Some other accumulator instructions are:
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then you can write, for immediate constants, "k → rS" or better "k → <rS: -->
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them because they are easier to remember as DEC and INC, Knuth used them in his
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The scripts are "near to formal". For formal ones we can imagine the use of a
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The DG2007 paper has the most illustrious bibliography I've ever appeared in.
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article. See the four-variable table of "func(i/d,rS,i/d,rD)" below. wvbailey
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All this is probably in Minsky's text but I haven't looked back at it yet.
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has been proposed since 2021 without objection, so I'd say go ahead and be
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is not adequate for universality in a CM with insufficiently-many registers
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A convention may be to fix a "reserved register" for use as rW (wasting).
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I have no idea where this is leading. I'm just following the scent. Bill
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10 DEC (2) 20 JZ (2,50) 30 INC (1) 40 JZ (0,10) 50 HALT
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1 CLR(rY) 2 JZ (rX,6) 3 INC(rY) 4 DEC(rX) 5 J (2) 6 CONTINUE
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the articles appear to show them from these different points of view.
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The simplest and ease to write (using wiki "#" mark for auto-addres):
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EXPonential, r=rX**rY; perhaps preserving the contents of rX and rY.
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func( d, A, k) e.g. LDA k; ADDA k; SUBA k; etc. CPY (d,k,A)= LDA k
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SUBtract, r=rX-rY; perhaps preserving the contents of rX and rY.
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MULtiply, r=rX*rY; perhaps preserving the contents of rX and rY.
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or Turing "N", but it specifies a register to test for 0 or 1:
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Find pictures for the biographies of computer scientists (see
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ftp://publications.ai.mit.edu/ai-publications/pdf/AIM-257.pdf
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Here we can fix "(for articles) standards". They are like on
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because it is a convention to be found in a published text
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Compare rX with rY and returns on r (r=0 if rX equal rY).
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Go to i (unconditional jump); register #0 must contain 0.
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I find the following is much more expressive: <rS: -->
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func( i, A, i, A) e.g. LDAiA (this is used by Schonhage!)
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r=rX+rY; perhaps preserving the contents of rX and rY.
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For a better layout and OPTIONAL use of "goto labels":
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Indirect copy Source contents to indirect Destination
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func( d, rs, i, rD) e.g. CPY (d, A, i, rD) = STAi rD,
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func( d, A, d, A) e.g. INCA, DECA, CLRA, LDAA = nop,
589:=0 (always zero), and a finite list of instructions 433:, a collaborative effort to improve the coverage of 82:, a collaborative effort to improve the coverage of 1845: 1597: 467:This article has not yet received a rating on the 190:Computer science articles needing expert attention 116:This article has not yet received a rating on the 582:, each of which can hold a non-negative integer, 1144:... in terms of JZ, DEC, J, CLR, INC, CPY, ADD. 1103:Copy rX into rY, rW must be free (at end rW=0). 2078:. In a book on line by Helmut Schwichtenberg, 906:means "contents of register S", <<rS: --> 857:func( d, A, i, rD) e.g. STAi rD CPY (<A: --> 695:articles. There are optional "clean styles". 548:The "RefTable", if used, probably should go on 543:means "contents of". If you write < rS : --> 2105:and bounded minimization." (p. 60). It is the 1482:issues, all recursive functions are certainly 1201:LoaDA; special register called "accumulator" 687:Algorithm presentation style (scripting style) 330:WikiProject Computer science/Unreferenced BLPs 8: 2338:Unknown-importance Computer science articles 2101:as those which omit the bounded product. 2033: 2030: 2027: 2024: 2021: 2018: 2015: 2012: 2009: 2006: 2003: 1995: 1992: 1989: 1986: 1983: 1980: 1977: 1974: 1971: 1968: 1965: 1957: 1954: 1951: 1948: 1945: 1942: 1939: 1936: 1933: 1930: 1927: 1919: 1916: 1913: 1910: 1907: 1904: 1901: 1898: 1895: 1892: 1889: 1817: 1814: 1812: 1810: 1807: 1804: 1802: 1799: 1797: 1795: 1793: 1790: 1788: 1786: 1783: 1781: 1778: 1776: 1769: 1767: 1764: 1761: 1758: 1756: 1753: 1750: 1747: 1744: 1741: 1739: 1736: 1733: 1730: 1727: 1724: 1721: 1713: 1710: 1707: 1704: 1701: 1698: 1695: 1692: 1689: 1686: 1683: 1680: 1677: 1674: 1671: 1668: 1665: 1662: 1406:Counter machines discussion moved here from 1262: 1256: 1248: 1243: 1235: 1230: 1222: 1219: 1211: 1208: 1200: 1197: 1182: 497:To be didactic on examples and comparations; 1253: 1249:Indirect copy contents of r to accumulator 1240: 1236:Indirect copy contents of r to accumulator 1227: 1216: 1205: 1194: 1130:... in terms of JZ, DEC, J, CLR, INC, CPY. 247:Computer science articles without infoboxes 185:Computer science articles needing attention 2223: 382: 151:Here are some tasks awaiting attention: 125: 47: 2074:I wanted to find out more about Kalmar's 2000: 1962: 1924: 1886: 1773: 1718: 1659: 1334:'Problems with the counter machine model' 1275:indicates indirect addressing; <r: --> 542:(Source and Destination) where < : --> 2171:both roller-sets right- and left-capable 1416:A Two Counter Machine Cannot Calculate 2 1183: 1180: 1087:Move rX to rY, clearing contents of rX. 959: 740: 1349: 676:; otherwise go to the next instruction. 384: 49: 19: 1223:StoreA in r: store contents of A in r 1212:Immediate constant k from instruction 644:by 1, then go to the next instruction. 625:by 1, then go to the next instruction. 96:Knowledge:WikiProject Computer science 2353:Unknown-priority mathematics articles 2343:WikiProject Computer science articles 1823:I need to reboot. I'll be back. Bill 1486:by a 2CM. If a 2CM is used with some 99:Template:WikiProject Computer science 7: 2093:Schwictenberg's version of Kalmar's 1541:Rich Schroeppel rcs@cs.arizona.edu 667:is zero. If so, jump to instruction 427:This article is within the scope of 76:This article is within the scope of 727:(and to use optional "goto labels") 564:Counter machine's referencial model 490:A reference model is necessary to: 38:It is of interest to the following 635:— decrement the value of register 616:— increment the value of register 266:Timeline of computing 2020–present 14: 2333:C-Class Computer science articles 2162:single-tape with two roller-sets, 2132:single-tape with two roller-sets, 1387:Knowledge:Algorithms on Knowledge 447:Knowledge:WikiProject Mathematics 292:Computing articles needing images 1321:article has to be reworked. The 450:Template:WikiProject Mathematics 414: 404: 386: 142: 69: 51: 20: 1300:Counter machine:Reference model 875:func( d, rS, d, A) e.g. LDAi rS 869:func( i, rS, d, A) e.g. STAi rS 486:Sugestion for Referencial model 863:func( d, A, d, rD) e.g. STA rD 1: 2274:20:30, 16 February 2024 (UTC) 2238:19:23, 21 November 2020 (UTC) 2212:01:46, 29 November 2007 (UTC) 2193:22:54, 23 November 2007 (UTC) 2050:18:31, 23 November 2007 (UTC) 1833:16:41, 23 November 2007 (UTC) 1589:02:09, 23 November 2007 (UTC) 1555:22:08, 21 November 2007 (UTC) 1500:13:50, 21 November 2007 (UTC) 1453:20:01, 20 November 2007 (UTC) 1434:machine can compute N, 2, log 1401:20:56, 13 November 2006 (UTC) 441:and see a list of open tasks. 346:Tag all relevant articles in 90:and see a list of open tasks. 2348:C-Class mathematics articles 935:04:19, 25 October 2006 (UTC) 914:04:19, 25 October 2006 (UTC) 557:04:43, 25 October 2006 (UTC) 540:I would prefer < rS : --> 525:04:57, 25 October 2006 (UTC) 500:To be objective and "clean". 494:Simplify model comparations; 355:WikiProject Computer science 131:WikiProject Computer science 79:WikiProject Computer science 2138:right-hand write-only head, 1189: 1186: 518:algorithm characterizations 286:List of computer scientists 2369: 2299:09:35, 24 April 2024 (UTC) 2168:right-hand read-only head, 2141:both roller-sets left-only 839:func( iS, rS, iD, rD) e.g. 699:"Ease to write" std styles 118:project's importance scale 2165:left-hand read-only head, 1422:. While he proves that a 734:"Better layout" std style 466: 399: 348:Category:Computer science 124: 115: 102:Computer science articles 64: 46: 2155:Collatz capable machine: 2135:left-hand read-only head 1008:IF rX=0 THEN i1 ELSE i2 966:Implementation (script) 845:func( i, rs, i, rD) e.g. 682:— halts the computation. 658:— check if the value of 469:project's priority scale 350:and sub-categories with 2316:19:02, 2 May 2024 (UTC) 1305:Transfer basic to there 944:microcoded instructions 430:WikiProject Mathematics 1563: 1375:Knowledge:Lead section 1187:Implementation script 311:Computer science stubs 28:This article is rated 1562: 1463:i/o convention in CMs 1381:Style for Algorithms! 1338:Random-access machine 1324:Counter-machine model 1254:CPY ( i, rS, i, rD ) 963:Emulated instruction 872:func( d, rs, i, A) ?? 866:func( i, rS, i, A) ?? 854:func( i, A, d, rD) ?? 851:func( i, A, i, rD) ?? 537:help translate them. 2109:that caught my eye. 2095:elementary functions 2080:Logic of Computation 2076:elementary functions 1358:Church-Turing thesis 1198:CPY (r) , A implied 1172:... in terms of ... 888:this is "irregular" 453:mathematics articles 129:Things you can help 1566:(Image inserted by 1257:CPY <<rS: --> 821:Referential Library 533:, a standard table 1564: 1369:Clean Lead section 1231:CPY <<r: --> 1220:CPY implied_A (r) 422:Mathematics portal 34:content assessment 2253:Counter automaton 2240: 2228:comment added by 2038: 2037: 1821: 1820: 1267: 1266: 1259:, <<rY: --> 1245:to <<r: --> 1179: 1178: 1071:CLEAR r; do r=0. 818: 817: 725:arbitrary address 693:Assembly language 483: 482: 479: 478: 475: 474: 381: 380: 377: 376: 373: 372: 369: 368: 2360: 2287: 2286: 2107:exponentiation 2 1846: 1598: 1361: 1354: 1181: 983: 960: 921:register machine 858:,<<rD: --> 827:register machine 741: 681: 657: 634: 615: 550:register machine 541:or < rD : --> 455: 454: 451: 448: 445: 424: 419: 418: 408: 401: 400: 390: 383: 359: 353: 228:Computer science 157:Article requests 146: 139: 138: 126: 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2126: 2099:sub-elementary 2087: 2083: 2068: 2064: 2060: 2056: 2036: 2035: 2032: 2029: 2026: 2023: 2020: 2017: 2014: 2011: 2008: 2005: 2002: 1998: 1997: 1994: 1991: 1988: 1985: 1982: 1979: 1976: 1973: 1970: 1967: 1964: 1960: 1959: 1956: 1953: 1950: 1947: 1944: 1941: 1938: 1935: 1932: 1929: 1926: 1922: 1921: 1918: 1915: 1912: 1909: 1906: 1903: 1900: 1897: 1894: 1891: 1888: 1884: 1883: 1880: 1877: 1874: 1871: 1868: 1865: 1862: 1859: 1856: 1853: 1850: 1844: 1843: 1840: 1819: 1818: 1816: 1813: 1811: 1809: 1806: 1803: 1801: 1798: 1796: 1794: 1792: 1789: 1787: 1785: 1782: 1780: 1777: 1775: 1771: 1770: 1768: 1766: 1763: 1760: 1757: 1755: 1752: 1749: 1746: 1743: 1740: 1738: 1735: 1732: 1729: 1726: 1723: 1720: 1716: 1715: 1712: 1709: 1706: 1703: 1700: 1697: 1694: 1691: 1688: 1685: 1682: 1679: 1676: 1673: 1670: 1667: 1664: 1661: 1657: 1656: 1653: 1650: 1647: 1644: 1641: 1638: 1635: 1632: 1629: 1626: 1623: 1620: 1617: 1614: 1611: 1608: 1605: 1602: 1596: 1595: 1572: 1543: 1542: 1538: 1537: 1532: 1531: 1527: 1526: 1525: 1524: 1517: 1516: 1515: 1514: 1503: 1502: 1435: 1410: 1404: 1382: 1379: 1370: 1367: 1363: 1362: 1348: 1347: 1343: 1342: 1341: 1330:spaghetti-code 1313: 1306: 1303: 1291: 1288: 1286: 1284: 1283: 1280: 1277: 1273:<<r: --> 1265: 1264: 1261: 1255: 1251: 1250: 1247: 1244:CPY <A: --> 1242: 1241:STA ( i, r ) 1238: 1237: 1234: 1229: 1228:LDA ( i, r ) 1225: 1224: 1221: 1218: 1214: 1213: 1210: 1207: 1203: 1202: 1199: 1196: 1192: 1191: 1188: 1185: 1177: 1176: 1173: 1170: 1163: 1162: 1159: 1156: 1149: 1148: 1145: 1142: 1135: 1134: 1131: 1128: 1121: 1120: 1117: 1114: 1112: 1105: 1104: 1101: 1098: 1096: 1089: 1088: 1085: 1082: 1080: 1073: 1072: 1069: 1068: 1067: 1064: 1059: 1052: 1051: 1048: 1047: 1046: 1043: 1038: 1031: 1030: 1027: 1026: 1025: 1022: 1017: 1010: 1009: 1006: 1005: 1004: 1001: 996: 989: 988: 985: 978: 971: 970: 967: 964: 955:C preprocessor 940: 939: 938: 937: 917: 916: 903: 899: 898: 897: 896: 895: 894: 886: 885: 884: 883: 882: 879: 876: 873: 870: 867: 864: 861: 855: 852: 849: 846: 843: 840: 822: 819: 816: 815: 814: 810: 807: 803: 802: 801: 797: 795: 791: 790: 789: 785: 783: 779: 778: 777: 773: 771: 767: 766: 765: 761: 760: 756: 752: 751: 748: 745: 735: 732: 729: 721: 720: 717: 714: 711: 708: 700: 697: 688: 685: 684: 683: 677: 671: 662: 645: 639: 626: 620: 600: 593: 586: 577: 570: 560: 505: 504: 501: 498: 495: 487: 484: 481: 480: 477: 476: 473: 472: 465: 459: 458: 456: 439:the discussion 426: 425: 409: 397: 396: 391: 379: 378: 375: 374: 371: 370: 367: 366: 364: 363: 361: 360: 343: 335: 333: 332: 326: 316: 314: 313: 307: 297: 295: 294: 289: 281: 271: 269: 268: 262: 252: 250: 249: 243: 233: 231: 230: 224: 214: 212: 211: 205: 195: 193: 192: 187: 181: 171: 169: 168: 162: 150: 148: 147: 135: 134: 122: 121: 114: 108: 107: 105: 88:the discussion 74: 62: 61: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 2365: 2354: 2351: 2349: 2346: 2344: 2341: 2339: 2336: 2334: 2331: 2330: 2328: 2317: 2313: 2309: 2305: 2302: 2301: 2300: 2296: 2292: 2288: 2278: 2277: 2276: 2275: 2271: 2267: 2263: 2259: 2254: 2250: 2243: 2241: 2239: 2235: 2231: 2230:95.151.103.43 2227: 2217: 2213: 2209: 2205: 2201: 2197: 2196: 2195: 2194: 2190: 2186: 2181: 2170: 2167: 2164: 2161: 2160: 2159: 2158: 2154: 2153: 2152: 2151: 2150: 2140: 2137: 2134: 2131: 2130: 2129: 2128: 2124: 2123: 2122: 2121: 2120: 2118: 2113: 2110: 2108: 2102: 2100: 2096: 2091: 2081: 2077: 2072: 2052: 2051: 2047: 2043: 2001:Jump-if-1 #: 1999: 1963:Jump-if-0 #: 1961: 1923: 1887:Instruction: 1885: 1847: 1841: 1837: 1836: 1835: 1834: 1830: 1826: 1772: 1717: 1660:Instruction: 1658: 1599: 1593: 1592: 1591: 1590: 1586: 1582: 1578: 1571: 1569: 1561: 1557: 1556: 1552: 1548: 1540: 1539: 1534: 1533: 1529: 1528: 1521: 1520: 1519: 1518: 1511: 1510: 1509: 1508: 1507: 1501: 1497: 1493: 1489: 1485: 1481: 1476: 1472: 1468: 1464: 1462: 1457: 1456: 1455: 1454: 1450: 1446: 1440: 1431: 1429: 1425: 1421: 1417: 1409: 1405: 1403: 1402: 1399: 1395: 1390: 1388: 1380: 1378: 1376: 1368: 1359: 1353: 1350: 1346: 1339: 1335: 1331: 1326: 1325: 1320: 1319: 1314: 1311: 1307: 1304: 1301: 1297: 1296: 1295: 1289: 1287: 1281: 1278: 1272: 1271: 1270: 1252: 1239: 1233:to <A: --> 1226: 1215: 1204: 1193: 1174: 1171: 1168: 1165: 1164: 1160: 1157: 1154: 1151: 1150: 1146: 1143: 1140: 1137: 1136: 1132: 1129: 1126: 1123: 1122: 1118: 1113: 1110: 1107: 1106: 1102: 1097: 1094: 1091: 1090: 1086: 1081: 1078: 1075: 1074: 1070: 1065: 1062: 1061: 1060: 1057: 1054: 1053: 1049: 1044: 1041: 1040: 1039: 1036: 1033: 1032: 1028: 1023: 1020: 1019: 1018: 1015: 1012: 1011: 1007: 1002: 999: 998: 997: 994: 991: 990: 986: 984: 979: 976: 973: 972: 968: 965: 962: 961: 958: 956: 951: 949: 945: 936: 933: 929: 928: 926: 925: 924: 922: 915: 912: 904: 901: 900: 892: 891: 890: 889: 887: 880: 877: 874: 871: 868: 865: 862: 856: 853: 850: 847: 844: 841: 838: 837: 836: 835: 832: 831: 830: 828: 820: 812: 811: 808: 805: 804: 800:JZ (r0,begin) 799: 798: 796: 793: 792: 787: 786: 784: 781: 780: 775: 774: 772: 769: 768: 763: 762: 758: 757: 754: 753: 749: 746: 743: 742: 739: 733: 728: 726: 718: 715: 712: 709: 706: 705: 704: 698: 696: 694: 686: 678: 674: 670: 665: 661: 655: 651: 646: 642: 638: 632: 627: 623: 619: 613: 608: 607: 606: 603: 599: 592: 585: 580: 576: 569: 565: 559: 558: 555: 551: 546: 538: 536: 532: 527: 526: 523: 519: 515: 511: 502: 499: 496: 493: 492: 491: 485: 470: 464: 461: 460: 457: 440: 436: 432: 431: 423: 417: 412: 410: 407: 403: 402: 398: 395: 392: 389: 385: 356: 349: 345: 344: 342: 340: 336: 331: 328: 327: 325: 323: 322: 317: 312: 309: 308: 306: 304: 303: 298: 293: 290: 287: 283: 282: 280: 278: 277: 272: 267: 264: 263: 261: 259: 258: 253: 248: 245: 244: 242: 240: 239: 234: 229: 226: 225: 223: 221: 220: 215: 210: 207: 206: 204: 202: 201: 196: 191: 188: 186: 183: 182: 180: 178: 177: 172: 167: 164: 163: 161: 159: 158: 153: 152: 149: 145: 141: 140: 137: 136: 132: 128: 127: 123: 119: 113: 110: 109: 106: 89: 85: 81: 80: 75: 72: 68: 67: 63: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 2303: 2248: 2247: 2224:— Preceding 2221: 2182: 2178: 2148: 2125:Tag machine: 2116: 2114: 2111: 2106: 2103: 2098: 2094: 2092: 2079: 2075: 2073: 2053: 2039: 1822: 1576: 1573: 1565: 1544: 1504: 1487: 1483: 1480:tractability 1479: 1474: 1470: 1466: 1460: 1459: 1441: 1432: 1427: 1423: 1415: 1412: 1393: 1391: 1384: 1372: 1352: 1344: 1333: 1322: 1316: 1294:Sugestions: 1293: 1285: 1268: 1166: 1152: 1138: 1124: 1108: 1092: 1076: 1055: 1034: 1029:DEC and JZ. 1013: 995:(rX, i1,i2) 992: 980: 974: 952: 941: 918: 824: 750:Instruction 737: 724: 722: 702: 690: 672: 668: 663: 659: 653: 649: 640: 636: 630: 621: 617: 611: 601: 597: 590: 583: 578: 574: 567: 563: 561: 547: 539: 534: 530: 528: 513: 506: 489: 428: 338: 337: 321:Unreferenced 319: 318: 300: 299: 274: 273: 255: 254: 236: 235: 217: 216: 198: 197: 174: 173: 155: 154: 77: 40:WikiProjects 2308:KenShirriff 2266:KenShirriff 1774:Jump-to #: 1577:Computation 1050:INC and J. 776:JZ (r2,end) 514:define them 444:Mathematics 435:mathematics 394:Mathematics 2327:Categories 1925:Register: 1719:Register: 1484:computable 1465:— namely, 1396:. wvbailey 1345:References 1217:STA ( r ) 1195:LDA ( r ) 1169:(rX,rY,r) 1155:(rX,rY,r) 1141:(rX,rY,r) 1127:(rX,rX,r) 1111:(rX,rY,r) 1003:JZ (r0,i2) 1000:JZ (rX,i1) 919:Different 1298:Create a 1190:Comments 1184:Mnemonic 982:JZ (r0,i) 969:Comments 716:JZ (0,1) 710:JZ (2,5) 209:Computing 2295:contribs 2283:Chaotıċ 2226:unsigned 2185:Wvbailey 2042:Wvbailey 1825:Wvbailey 1568:Wvbailey 1547:Wvbailey 1445:Wvbailey 1398:Wvbailey 1340:article. 1302:article. 1095:(rX,rY) 1079:(rX,rY) 1066:JZ (r,1) 1024:JZ (r,i) 948:emulator 932:Wvbailey 911:Wvbailey 909:wvbailey 829:models. 723:Or, for 554:Wvbailey 522:Wvbailey 257:Maintain 200:Copyedit 2262:WP:BOLD 2249:Support 2117:appears 1360:is true 1356:if the 1308:Update 1290:Working 1269:Notes: 788:INC(r1) 764:DEC(r2) 713:INC (1) 707:DEC (2) 238:Infobox 176:Cleanup 30:C-class 2304:Oppose 2251:: The 2204:r.e.s. 2086:ELSE I 2069:y<w 2065:y<w 1581:r.e.s. 1492:r.e.s. 1206:LDA k 1063:DEC(r) 1045:J (i) 1042:INC(r) 1037:(r,i) 1021:DEC(r) 1016:(r,i) 946:for a 747:Label 219:Expand 36:scale. 2258:merge 2040:Bill 1911:test 1545:Bill 1513:'net. 1488:other 1424:three 1274:: --> 1260:: --> 1258:: --> 1246:: --> 1232:: --> 1014:DECJZ 907:: --> 859:: --> 759:begin 744:Addr 562:The " 535:would 302:Stubs 276:Photo 133:with: 2312:talk 2291:talk 2285:Enby 2270:talk 2234:talk 2208:talk 2189:talk 2046:talk 1920:dcr 1917:inc 1914:dcr 1908:inc 1905:inc 1902:inc 1899:dcr 1896:inc 1893:dcr 1890:out 1829:talk 1708:inc 1705:dcr 1696:dcr 1690:inc 1687:inc 1684:inc 1678:inc 1675:dcr 1669:dcr 1663:out 1585:talk 1551:talk 1496:talk 1475:only 1449:talk 1385:See 1373:See 1315:The 1058:(r) 1035:INCJ 977:(i) 813:HALT 809:end 719:HALT 680:HALT 648:JZ ( 629:DEC( 610:INC( 596:... 573:... 2218:DEC 2067:, Π 2061:y=w 2059:, Π 2057:y=w 2034:10 2031:11 1993:11 1975:10 1882:11 1879:10 1815:14 1779:14 1702:jz 1693:jz 1672:jZ 1666:jZ 1655:18 1652:17 1649:16 1646:15 1643:14 1640:13 1637:12 1634:11 1631:10 1461:the 1167:SUB 1153:EXP 1139:MUL 1125:ADD 1109:CMP 1093:CPY 1077:MOV 1056:CLR 806:50 794:40 782:30 770:20 755:10 531:But 510:MIX 463:??? 112:??? 2329:: 2314:) 2297:) 2293:· 2272:) 2236:) 2210:) 2191:) 2048:) 2028:5 2025:9 2022:8 2019:7 2016:6 2013:2 2010:4 2007:3 2004:2 1996:1 1990:5 1987:1 1984:8 1981:7 1978:6 1972:4 1969:6 1966:2 1958:B 1955:A 1952:B 1949:B 1946:A 1943:A 1940:A 1937:A 1934:B 1931:A 1928:A 1876:9 1873:8 1870:7 1867:6 1864:5 1861:4 1858:3 1855:2 1852:1 1831:) 1808:1 1805:8 1800:1 1791:2 1784:9 1765:A 1762:B 1759:B 1754:B 1751:B 1748:A 1745:A 1742:A 1737:B 1734:A 1731:A 1728:A 1725:A 1722:A 1714:H 1711:j 1699:j 1681:j 1628:9 1625:8 1622:7 1619:6 1616:5 1613:4 1610:3 1607:2 1604:1 1587:) 1570:) 1553:) 1498:) 1469:— 1451:) 1389:. 1377:. 993:JZ 652:, 358:}} 352:{{ 2310:( 2289:( 2268:( 2232:( 2206:( 2187:( 2088:n 2084:m 2055:Σ 2044:( 1827:( 1583:( 1575:( 1549:( 1494:( 1447:( 1436:2 975:J 860:) 673:z 669:I 664:j 660:r 656:) 654:z 650:j 641:j 637:r 633:) 631:j 622:j 618:r 614:) 612:j 602:m 598:I 594:0 591:I 587:0 584:r 579:n 575:r 571:1 568:r 471:. 341:: 324:: 305:: 288:) 279:: 260:: 241:: 222:: 203:: 179:: 160:: 120:. 42::

Index


content assessment
WikiProjects
WikiProject icon
Computer science
WikiProject icon
WikiProject Computer science
Computer science
the discussion
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project's importance scale
WikiProject Computer science

Article requests
Requested articles/Applied arts and sciences/Computer science, computing, and Internet
Cleanup
Computer science articles needing attention
Computer science articles needing expert attention
Copyedit
Computing
Expand
Computer science
Infobox
Computer science articles without infoboxes
Maintain
Timeline of computing 2020–present
Photo
List of computer scientists
Computing articles needing images
Stubs

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