hello every body

  i wrote this code:

restart;

with(MmaTranslator[Mma]):
with(Student[NumericalAnalysis]):
with(DEtools, FunctionDecomposition):
with(linalg):with(ArrayTools):
with(LinearAlgebra):

n:=3 ;

  a:=(r)->q[r](t):
  x[1]:=Vector[row](n,a);