| Title: | Mathematics at DEC |
| Moderator: | RUSURE::EDP |
| Created: | Mon Feb 03 1986 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2083 |
| Total number of notes: | 14613 |
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Dear Fellow Math Noters,
Is there a general catalog available of practical applications for the
Modulo-Inverse that is described here in Note 5 and its replies? I have
a general feeling that this algoritm has a lot of problem-solving power
just waiting to be tapped somewhere. Just for what it's worth, and thanks
for your help out there.
Dick Martin
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1773.1 | VMSDEV::HALLYB | Fish have no concept of fire | Tue Jul 13 1993 15:23 | 1 | |
This is referring to note 5 in HEAVY::ALGORITHMS (q.v.) | |||||
| 1773.2 | CFSCTC::GILBERT | Fri Jul 30 1993 21:14 | 12 | ||
FWIW, I developed an incredibly short algorithm for doing this modulo a power of two -- in particular, the machine's word size. This was for a matrix package that would invert a matrix in place. Since the interface passed the array by VMS descriptor, I had to consider arrays of *integers*. NB: In this case, only odd integers had inverses, and only matrices with odd determinants had inverses. I suggested using this in BASIC's run-time, but it was decided to keep what was there, which after considerablr work would produce an array of almost all zeroes. Is there any use? Perhaps. | |||||
| 1773.3 | RDVAX::GRIES | Tue Aug 03 1993 12:40 | 9 | ||
! FWIW, I developed an incredibly short algorithm for doing this modulo a ! power of two -- in particular, the machine's word size. Ok I bite, I am always interested in fast (if that is what short means) algorithms. If you post your code, I will be thankful. Gries | |||||
| 1773.4 | CFSCTC::GILBERT | Wed Aug 04 1993 20:20 | 1 | ||
See note 170. | |||||