Let’s have some multivariable polynomials P1 and P2 represented by TaylorN variable from TaylorSeries package, e.g.

```
using TaylorSeries
x, y = set_variables("x y")
P1 = TaylorN([HomogeneousPolynomial([1]), HomogeneousPolynomial([2, 3])], 3)
P2 = TaylorN([HomogeneousPolynomial([1]), HomogeneousPolynomial([0, 2])], 3)
```

Then let’s have another polynimial Q in different coordinates, e.g.

```
u, v = set_variables("u v")
Q = TaylorN([HomogeneousPolynomial([1]), HomogeneousPolynomial([1, 1])], 3)
```

Now I would like to get from polynomial Q in variables u, v another polynomial in variables x, y by substitution

u = P1(x,y)

v = P2(x,y)

Do you have any ideas how to do that? Thanks!