Missing evaluate for matrix

[albinahlback]

I think I should be able to do this:

julia> P, x = PolynomialRing(QQ, 2)
(Multivariate polynomial ring in 2 variables over QQ, QQMPolyRingElem[x1, x2])

julia> F = FractionField(P)
Fraction field
  of multivariate polynomial ring in 2 variables over QQ

julia> M = MatrixSpace(F, 2, 2)
Matrix space of 2 rows and 2 columns
  over fraction field of multivariate polynomial ring

julia> m = M()
[0   0]
[0   0]

julia> m[1, 1] = x[1]^2 + x[2]
x1^2 + x2

julia> m
[x1^2 + x2   0]
[        0   0]

julia> evaluate(m, [1; 2])

However, no method evaluate exists for this.

[thofma]

julia> map(p -> evaluate(p, [1, 2]), m)
[3   0]
[0   0]

I am a bit reluctant to add it, since we usually don't add extra methods, if it is just a (simple) application of map.

[fieker]

I agree with Tommy - as this is yet another example of induced actions...what about a univariate polynomial ring over your bivariate one: should evaluate then work as well and apply to the coeffs?

[albinahlback]

Alright, sounds reasonable!