Re: multiplying matrice rows

*To*: mathgroup at smc.vnet.net*Subject*: [mg44355] Re: multiplying matrice rows*From*: poujadej at yahoo.fr (Jean-Claude Poujade)*Date*: Wed, 5 Nov 2003 10:02:27 -0500 (EST)*References*: <bo7o7e$af9$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Dragutin Culinovic <dragutin.culinovic at fsb.hr> wrote in message news:<bo7o7e$af9$1 at smc.vnet.net>... > How can I to multiply enumerated list of rows of an matrice on following > way: > To multyply each row (except rows a,b and c)of matrice A withe row a of > the same matrice, and replace that row (not a row) with result. > > rows b and c are last rows, row a is any row in the range 1->b(exclusive) > > THX Example of solution with your notation : In[1]:= m = {{m11,m12},{m21,m22},{m31,m32},{m41,m42},{m51,m52}}; In[2]:= a=2; b=4; In[3]:=MapAt[#*m[[a]]&, m, Table[{i},{i, a+1, b-1}]] Out[3]={{m11,m12},{m21,m22},{m21 m31,m22 m32},{m41,m42},{m51,m52}} --- jcp