Hi. I am using JetCalclulus to prolong infinitesimal generators.

Then I want to find invariants, it means I want to act on some function by these differential operators and to solve linear PDEs.

Is it possible to do it automatically?

Let say I have a linear system of equations with 28 unknowns (Z1, Z2, ..., Z28).

I know that dimension of space of solution > 0. I want for all unknowns to be expressed only by (let say: Z20, Z21, ..., Z28).

How to specify these free variables? I'm pretty sure it is implemented in Maple.

Sometimes I got an error (purple in output). How can I catch on programming level?

I mean I want to do smth like: if <error> -> then <action>