### Variable Matrices on Sage

I am using Sagemath 10. I wish to work with matrices whose entries are multivariate polynomial ring variables (nothing funky with the base ring, `R = PolynomialRing(QQ, 100, 'x'); R.gens()`

is what I am trying). I create a `matrix.zero(n,n)`

for reasonable `n`

(currently just 3) and then try to alter each entry manually. However, Sage complains that the entries can't be non-constant polynomials.

So I tried to provide the ring above as an argument by writing `matrix.zero(R, n,n)`

, but this generated the error

`TypeError: unbound method Parent.category() needs an argument`

I have also tried using `M=MatrixSpace(R,n,n); M(L)`

where `L`

is a list of appropriate design. It still complains about getting non-constant polynomial entries.

How do I circumvent this issue? I only plan to analyse the determinant of a specific kind of matrix. Based on this information, feel free to offer alternatives with more restricted functionality than just a matrix. Thank you!