I have a vector say a 9×9 vector which looks: \begin{align} \begin{pmatrix} 2x +1 \ x \ 1 \ x \ x^2 + 2x \ 2x \ x\ 2x^2 \ 0 \ \end{matrix} \end{align} These entries in F3[x] . There are 9 rows in this matrix and i want to write a function which takes an n2×1 matrix and turns it into a n×n matrix. So, in this case, we want the function would turn the above vector into
\begin{align} [2x+1x1 ] \end{align} \begin{align} [xx2+2x2x ] \end{align} \begin{align} [x2x20 ] \end{align}
In this sage, I tried this: sage: v = Matrix(GF(3)[x], [[2x+1],[x],[1],[x],[x^2+2x],[2x],[x],[2x^2],[0]]) Then, write the following: sage: Matrix(v.base_ring(), 3, 3, v)
This gave an error: inconsistent number of rows: should be 3 but got 1