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 Author Comment/Response Forum Moderator email me 09/19/06 06:00am Look at the Dimensions of you matrix and recall how matrix dimensions are refered to in general mathematics, i.e. n X m. From what you write, I am guessing that you have a flat list such as {1,2,3} In[]:= Dimensions[{1,2,3}] Out[]= {3} Now consider: In[]:= a = {{1, 2, 3}} Out[]= {{1, 2, 3}} In[]:= Dimensions[a] Out[]= {1,3} In[] := aT = Transpose[a] Out[]= {{1}, {2}, {3}} In[]:= Dimensions[aT] Out[]= {3,1} These dimensions match the standard requirement for dot products: Look at the "shape": In[]:= MatrixForm[a] Out[]//MatrixForm= 1 2 3 In[]:= MatrixForm[aT] Out[]//MatrixForm= 1 2 3 Now the Dot product: In[]:= a . aT Out[]= {{14}} URL: ,

 Subject (listing for 'Do I Dot product?') Author Date Posted Do I Dot product? Prashanth 09/17/06 4:47pm Correcting my question Prashanth 09/18/06 10:17pm Re: Do I Dot product? Bob 09/19/06 02:32am Re: Do I Dot product? Forum Modera... 09/19/06 06:00am
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