Re: Convert nxn matrix to a column vector with (n^2) elements

*To*: mathgroup at smc.vnet.net*Subject*: [mg83731] Re: Convert nxn matrix to a column vector with (n^2) elements*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Thu, 29 Nov 2007 06:26:05 -0500 (EST)*Organization*: The Open University, Milton Keynes, UK*References*: <fiji4u$ijb$1@smc.vnet.net>

Tara.Ann.Lorenz at gmail.com wrote: > Any ideas how to convert an nxn matrix to a column vector with n^2 > elements? Beware that Mathematica does not have any special construct to distinguish row vectors from column vectors. A vector can be represented by a one dimensional list made of numeric or/and symbolic elements. Depending on the context and the operation in use, Mathematica interprets the vector as a column or a row vector. (More generally, vectors are tensors of rank 1.) Having said that, I believe that what you are looking for is a command of the form Flatten@Transpose@m (m being your square matrix) as illustrated in the following example: Mathematica 6.0 for Microsoft Windows (32-bit) Copyright 1988-2007 Wolfram Research, Inc. In[1]:= m = Array[a, {2, 2}] Out[1]= {{a[1, 1], a[1, 2]}, {a[2, 1], a[2, 2]}} In[2]:= %//MatrixForm Out[2]//MatrixForm= a[1, 1] a[1, 2] a[2, 1] a[2, 2] In[3]:= Flatten@Transpose@m Out[3]= {a[1, 1], a[2, 1], a[1, 2], a[2, 2]} In[4]:= %//MatrixForm Out[4]//MatrixForm= a[1, 1] a[2, 1] a[1, 2] a[2, 2] In[5]:= Flatten@m Out[5]= {a[1, 1], a[1, 2], a[2, 1], a[2, 2]} In[6]:= %//MatrixForm Out[6]//MatrixForm= a[1, 1] a[1, 2] a[2, 1] a[2, 2] Regards, -- Jean-Marc