R help - Oct 2011 - matrix multiplication

Dear all, 
Sorry to bother you with such a stupid question, but I just cannot find the
solution to my problem.

I'd like to use matrix multiplication for meanA and factorial 3. 
I use the command meanA%*%factorial 3. 
But everything I get is: Error in factorial3 %*% A : non-conformable
arguments

I know that the number of the columns of the first vector has to be the same
number of rows of the 
second vector to be able to use matrix multiplication, but that is the case
here. I also tried it with 
two columns for factorial 3 and that didnt work either. 

Can someone help me out with this?'

these are my matrices:

meanA
         [,1]     [,2]
[1,] 3.666667 4.666667
> factorial3
     [,1]
[1,]    1

Thank you so much!
Cheers, maria

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Your question as answered by Timothy in your previous thread 

http://r.789695.n4.nabble.com/Re-Creating-the-mean-using-algebra-matrix-td3895689.html



flokke wrote:
> 
> Dear all, 
> Sorry to bother you with such a stupid question, but I just cannot find
> the solution to my problem.
> 
> I'd like to use matrix multiplication for meanA and factorial 3. 
> I use the command meanA%*%factorial 3. 
> But everything I get is: Error in factorial3 %*% A : non-conformable
> arguments
> 
> I know that the number of the columns of the first vector has to be the
> same number of rows of the 
> second vector to be able to use matrix multiplication, but that is the
> case here. I also tried it with 
> two columns for factorial 3 and that didnt work either. 
> 
> Can someone help me out with this?'
> 
> these are my matrices:
> 
> meanA
>          [,1]     [,2]
> [1,] 3.666667 4.666667
> 
>> factorial3
>      [,1]
> [1,]    1
> 
> Thank you so much!
> Cheers, maria
> 

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On 12/10/11 09:11, flokke wrote:
> Dear all,
> Sorry to bother you with such a stupid question, but I just cannot find the
> solution to my problem.
>
> I'd like to use matrix multiplication for meanA and factorial 3.
> I use the command meanA%*%factorial 3.
> But everything I get is: Error in factorial3 %*% A : non-conformable
> arguments
>
> I know that the number of the columns of the first vector
     first ***MATRIX***
> has to be the same
> number of rows of the
> second vector
     second ***MATRIX***
> to be able to use matrix multiplication, but that is the case
> here.
     No it isn't!!!  Your ``factorial3'' has ***one*** row, and
     ``meanA'' has ***two*** columns.  So the arrays are
     not conformable, just like the error message says!

     There are three sorts of people; those who can count,
     and those who can't!
> I also tried it with
> two columns for factorial 3 and that didnt work either.
     Try it with two ***rows*** for factorial3!!!

     And watch those spaces in names.  They don't
belong.
> Can someone help me out with this?'
>
> these are my matrices:
>
> meanA
>           [,1]     [,2]
> [1,] 3.666667 4.666667
>
>> factorial3
>       [,1]
> [1,]    1
To repeat:  (1 x 2) times (1 x 1) doesn't work.
Note that (n x 2) times (2 x m) *does* work, and gives an (n x m) result.

     cheers,

         Rolf Turner