Opened 12 years ago
Closed 12 years ago
#280 closed bug (fixed)
BUG in realrad.lib
Reported by: | gorzel | Owned by: | gorzel |
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Priority: | minor | Milestone: | 3-1-2 and higher |
Component: | singular-libs | Version: | 3-1-1 |
Keywords: | Cc: |
Description
1.) In 2008, a bug was found in realrad.lib
See: Real solutions
http://www.singular.uni-kl.de/forum/viewtopic.php?f=10&t=1678
Some month ago, I described the problem and how to solve it, put it has not be fixed yet.
Furthermore:
2.) the static proc exp is buggy
proc exp(int a, int b) // <-- a should be bigint { number res = 1; // <--this should be bigint while (b > 0) { if (b mod 2 == 1) { res = res * a; b = b-1; } a = a * a; b = b div 2; } return(res); }
is buggy
> exp(2,34); // ** int overflow(*), result may be wrong 0
but obsolete.
It is only used in the static proc subsets to compute 2^{n, }
int grenze=int(exp(2,n))-1;
However this can be done just by
int grenze = int(bigint(2)^n-1);
Though, a list with MAXINT =2^{31-1 entries can not be handled I guess }
Remarl: The static proc binlog is never used.
3.) fix the typo in the help string
proc decision(poly f) " USAGE: decission(f); <-- decision
4.) shouldn't Silke Spang's email adress be given at AUTHOR field ?
Change History (3)
comment:1 Changed 12 years ago by
Owner: | changed from anne to someone |
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comment:2 Changed 12 years ago by
Owner: | changed from someone to gorzel |
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comment:3 Changed 12 years ago by
Resolution: | → fixed |
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Status: | new → closed |
The real solution would be the use of ringlist, but for the moment the proposed changes (from the forum) are used.
Thanks for letting us know. Could you please check out, modify the lib and check in again? Best regards from the SINGULAR team