Question: is DETools:-matrixDE broken?

or am I missing something?


A:=Matrix(2, 2, [1, 4, 5, 1]);
x0:=Vector([2,1]); #initial condition

sol := DETools:-matrixDE(A, t);

M:=(Matrix(convert(sol[1], listlist)));  #convert to modern day Matrix from array that is returned by matrixDE

#the solutoion according to the documentation:


#should match x0 at t=0, but does not:

subs(t=0, x);


#using this instead seems to work. But the docs claim this is method is meant to work for constant coeffs.

sol := DETools:-matrixDE(A, t, method=matrixexp);


Am i missing something? or is matrixDE not to be trusted (especially in cases where method is not provided)?

as a side note, the documentation is very out of date; claims matrixDE returns Matrix and vector, but these are just the old array types; means LinearAlgebra operations do not work.



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