Re: adding matrices

*To*: mathgroup at smc.vnet.net*Subject*: [mg65797] Re: adding matrices*From*: "J Siehler" <jsiehler at gmail.com>*Date*: Mon, 17 Apr 2006 02:28:53 -0400 (EDT)*References*: <e1sv6v$ct3$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

>if i type m-p, mathematica treats the second matrix p as a scalar and subtracts that entire 3x3 >matrix p from each entry of m If m and p have the same dimensions then Mathematica will subtract (or add) entry-by-entry the way you want. You might want to clarify what you mean by "subtracts [a matrix] from each 3x3 entry m" because that's a little unclear; better, post your code so we can see what's happening. -- In[8]:= m=Array[Random[Integer,{-10,10}]&,{3,3}] p=Array[Random[Integer,{-10,10}]&,{3,3}] Out[8]= {{6,1,-7},{2,9,-3},{1,1,8}} Out[9]= {{1,9,5},{-3,-10,9},{9,5,6}} In[10]:= m-p Out[10]= {{5,-8,-12},{5,19,-12},{-8,-4,2}}