Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1996
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 1996

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Inverse????

  • To: mathgroup at smc.vnet.net
  • Subject: [mg5499] Re: [mg5477] Inverse????
  • From: Daniel Lichtblau <danl>
  • Date: Sat, 14 Dec 1996 19:26:04 -0500
  • Organization: wolfram.com
  • Sender: owner-wri-mathgroup at wolfram.com

Hou-shou Chen wrote:
> 
> A matrix a={{0,0,1},{0,0,1},{1,1,1}} which is singular in Z_2, but
> Inverse commands gives the "result":
> 
> Inverse[a,Modulus->2]=
> {{0, 1, 1}, {1, 1, 0}, {1, 0, 0}}.
> 
> Is anything wrong ?
> 
> Houshou

Yes. It was a bug. Fixed in version 3.0.

In[5]:= a={{0,0,1},{0,0,1},{1,1,1}};

In[6]:= Det[a, Modulus->2]
Out[6]= 0

In[7]:= Inverse[a,Modulus->2]
Inverse::sing: Matrix {{0, 0, 1}, {0, 0, 1}, {1, 1, 1}} is singular.
Out[7]= Inverse[{{0, 0, 1}, {0, 0, 1}, {1, 1, 1}}, Modulus -> 2]

Daniel Lichtblau
Wolfram Research
danl at wolfram.com


  • Prev by Date: animating a PDE
  • Next by Date: Calculating Sums Of Roots For Trans. Functions
  • Previous by thread: Re: Inverse????
  • Next by thread: RSA and PowerMod-Function