On 6/19/08, Philippe Boeraeve <philippe.boeraeve at gmail.com> wrote:
> after having changed some elements of a matrix, I would like to show its
> content. I didn't found another solution that using genmatrix function. Is
> there another way?
> when copying values of a matrix in another one, the result is within brakets
> and the resulting matrix is not recognised as a matrix by maxima. For
> example, if I try to copy it, I get an error.
Phillippe, I'm sorry that the treatment of matrices is so confusing in
Maxima. It appears that the problem is that lists and arrays appear
in your program, but not matrices. In Maxima, lists and arrays are
distinct from matrices. To create a matrix, write matrix([...], [...], ...).
Note that [...] is a list; if you want a matrix of one row, write
matrix([...]). Also if you write foo[i, j] : 1234 before constructing foo
somehow, then foo is a so-called undeclared array (a kind of hash
table), not a matrix. Also note that the period "." is noncommutative
matrix multiplication while "*" is commutative.
I'm not sure what you 're trying to accomplish, but perhaps this helps.
best
Robert Dodier