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Topic review - Bugs in matrix code?
Author Message
wienand
  Post subject:   Reply with quote
Dear Justin Walker,

the Singular command minor is mainly intended for computing the ideal spanned by all the minors. Thus Singular does not care about signs.

Sincerely,

Oliver Wienand
Post Posted: Tue Sep 20, 2005 5:00 pm
Justin C. Walker
  Post subject:  Bugs in matrix code?  Reply with quote
This seems like a bug to me. Working with matrices, I get the following from Singular:

> m;
1,2,3,
4,5,6,
7,8,9
> minor(m,2);
_[1]=-3
_[2]=-6
_[3]=-6
_[4]=-12
_[5]=3
_[6]=6
_[7]=-3
_[8]=-6
_[9]=3

From hand computation, I get
-3, +6, -3, +6, -12, +6, -3, +6, -3

Are we working from different definitions, or am I just off base?

Regards,

Justin


email: justin@mac.com
Posted in old Singular Forum on: 2005-04-25 02:30:46+02
Post Posted: Thu Aug 11, 2005 5:33 pm


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