Re: MatrixReplace.m
- To: mathgroup at smc.vnet.net
- Subject: [mg25037] Re: MatrixReplace.m
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Fri, 1 Sep 2000 21:57:44 -0400 (EDT)
- References: <8onep9$ol4@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Giovanni, 1 becomes the 2 by 2 identity matrix -- Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 "Giovanni Scoglio" <g_scoglio at yahoo.it> wrote in message news:8onep9$ol4 at smc.vnet.net... > Hi everybody > > Roger Kirchner in MatrixReplace.m > (http://mathsource.wri.com/Content/Enhancements/Algebraic/0202-284) > says : > > " MatrixReplace[f[x], x -> A] returns f[A], where > multiplication > is matrix multiplication. " > > Well, let mat = {{1, 2}, {2, 3}} > > MatrixPower[mat, 3] gives > {{21, 34}, {34, 55}} :-) > > and 1 + MatrixPower[mat, 3] gives > {{22, 35}, {35, 56}} :-) > > Why does MatrixReplace[1 + x^3, x -> mat] return > {{22, 34}, {34, 56}} instead ? :-( > > It this a bug ? Is there something unclear to me in > the concept of matrix function ? > > Buon lavoro a tutti ! > Giovanni Scoglio > > ______________________________________________________________________ > Do You Yahoo!? > Il tuo indirizzo gratis e per sempre @yahoo.it su http://mail.yahoo.it >