Re: Matrix Inverse Issue

*To*: mathgroup at smc.vnet.net*Subject*: [mg80623] Re: Matrix Inverse Issue*From*: Bill Rowe <readnewsciv at sbcglobal.net>*Date*: Sun, 26 Aug 2007 23:22:59 -0400 (EDT)

On 8/26/07 at 3:00 AM, brg at nowhere.org (Brian Gladman) wrote: >I am having a problem with the matrix inverse for the following >matrix in Mathematica 6: >A = Table[If[j == i, 1 - i/10, If[j == i + 1, i/10, 0]], {i, 9},= {j, >9}] >A Inverse[A] >I expected the identity matrix here but I get extra terms. >Am I doing something wrong? Yes. A Inverse[A] does an element by element multiplication. You want A.Inverse[A] which does a matrix multiplication and gives the expected result -- To reply via email subtract one hundred and four