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Groups > comp.lang.forth > #135098
| Date | 2026-05-26 15:53 +1000 |
|---|---|
| Subject | Re: Forth for a balanced ternary machine |
| Newsgroups | comp.lang.forth |
| References | <10v1h24$1adtp$1@dont-email.me> <2026May25.201036@mips.complang.tuwien.ac.at> |
| From | dxf <dxforth@gmail.com> |
| Message-ID | <6a153548$1@news.ausics.net> (permalink) |
| Organization | Ausics - https://newsgroups.ausics.net |
On 26/05/2026 4:10 am, Anton Ertl wrote: > Matthias Koch <m.cook@gmx.net> writes: > ... > |In balanced ternary, a right shift is exactly the same as symmetric > |division by powers of three, unlike binary in which right-shifting > |negative two-complement numbers to divide by powers of two gives > |rounding artifacts. > > Floored division is not any more a rounding artifact than symmetric > division is. Whether to use floored or symmetric division depends on > the application. That's why we have FM/MOD and SM/REM in the > standard. The Forth-83 committee was so strongly in favour of floored > that they broke compatibility with Forth-79 because of that. > > Gforth since 0.7 implements / and other division words where Forth-94 > allows the system to choose as floored division words. This means > that in Gforth, "2 /" is equivalent to 2/ (which is defined as a shift > right by 1 bit): > > -3 2 / . \ prints -2 > -3 2/ . \ prints -2 Which is all very nice until beginners ask how that makes any sense ;-) ANS at least tells you 2* 2/ are bit-shifters with historic, albeit misleading, names.
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Forth for a balanced ternary machine Matthias Koch <m.cook@gmx.net> - 2026-05-25 14:58 +0200
Re: Forth for a balanced ternary machine anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-25 18:10 +0000
Re: Forth for a balanced ternary machine dxf <dxforth@gmail.com> - 2026-05-26 15:53 +1000
Re: Forth for a balanced ternary machine anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-26 07:46 +0000
Re: Forth for a balanced ternary machine dxf <dxforth@gmail.com> - 2026-05-27 00:52 +1000
Teaching Scenarios [Re: Forth for a balanced ternary machine] Buzz McCool <buzz_mccool@yahoo.com> - 2026-05-26 08:52 -0700
Re: Teaching Scenarios [Re: Forth for a balanced ternary machine] dxf <dxforth@gmail.com> - 2026-05-28 21:03 +1000
Re: Teaching Scenarios [Re: Forth for a balanced ternary machine] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-30 20:16 +0000
Re: Teaching Scenarios [Re: Forth for a balanced ternary machine] minforth <minforth@gmx.net> - 2026-05-31 11:02 +0200
Re: Teaching Scenarios [Re: Forth for a balanced ternary machine] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-31 14:13 +0000
Division (was: Forth for a balanced ternary machine) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-30 18:23 +0000
Re: Division dxf <dxforth@gmail.com> - 2026-05-31 12:49 +1000
Re: Division anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-31 14:20 +0000
Re: Division dxf <dxforth@gmail.com> - 2026-06-01 12:47 +1000
arithmetic shift right (was: Division) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-05-31 14:43 +0000
Re: arithmetic shift right dxf <dxforth@gmail.com> - 2026-06-01 18:18 +1000
Re: Forth for a balanced ternary machine Hans Bezemer <the.beez.speaks@gmail.com> - 2026-06-01 23:23 +0200
Re: Forth for a balanced ternary machine Matthias Koch <m.cook@gmx.net> - 2026-05-28 13:36 +0200
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