infinity expression from matrix inverse

*To*: mathgroup at smc.vnet.net*Subject*: [mg49800] infinity expression from matrix inverse*From*: "Xiao Huang" <xiaohda at hotmail.com>*Date*: Sun, 1 Aug 2004 04:10:03 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Dear Friends, Recently I've been having this problem with Mathematica 5.0: In the follwing program, when I set t=2 to 11, mathematica can give me the inverse of matrix n0, but for t >=12, it fails to produce the inverse due to infinity expressions. Can anyone explain this to me? (I guess the problem occurs in the last line.) Thanks a lot! Those a1,a2,n0,n0s,nn,c you see in the following program are just some matrices. Best Regards, Xiao \!\(<< LinearAlgebra`MatrixManipulation`\[IndentingNewLine] \(Remove["\<Global`*\>"];\)\[IndentingNewLine] \(ó = 8;\)\[IndentingNewLine] \(t = 11;\)\[IndentingNewLine] \(â = 0.6;\)\[IndentingNewLine] \(a1 = AppendRows[\ \ \ \ IdentityMatrix[\ t - 1\ ]\ , \ \ \ Table[\ 0\ , \ \ {\ t - 1\ }, \ {\ 1\ }\ ]\ \ \ \ ];\)\[IndentingNewLine] \(a2 = AppendRows[\ \ \ \ Table[\ 0\ , \ {\ t - 1\ }, \ {\ 1\ }\ ]\ , \ \ \ IdentityMatrix[\ t - 1\ ]\ \ \ \ \ ];\)\[IndentingNewLine] \(nn = Transpose[a1] . a1;\)\[IndentingNewLine] \(n1 = Transpose[a1] . a2;\)\[IndentingNewLine] \(c = IdentityMatrix[t] + AppendColumns[\ Table[0, \ {1}, \ {t}], AppendRows[\ \ \(-â\)*IdentityMatrix[t - 1], \ Table[\ 0, \ {t - 1}, \ {1}\ ]\ ]\ ];\)\[IndentingNewLine] \(vc = ó\^2*Inverse[c] . Transpose[Inverse[c]];\)\[IndentingNewLine] \(n0 = IdentityMatrix[t]\ + \ 2 x*vc . nn;\)\[IndentingNewLine] \(Print[\ MatrixForm[n0]\ ];\)\[IndentingNewLine] \(n2 = Inverse[n0] . vc;\)\[IndentingNewLine] \) _________________________________________________________________ Don?t just search. Find. Check out the new MSN Search! http://search.msn.click-url.com/go/onm00200636ave/direct/01/

**Follow-Ups**:**Re: infinity expression from matrix inverse***From:*Daniel Lichtblau <danl@wolfram.com>