I have a polynomials of multivariable for instance: $P=yx+2^4xy+3+5^2xz+3^4zx $

Now I would like to do the following:

  1. extract those temrs that only has $z$ .

  2. extract terms that only has $y$

  3. express my polynomial with something like this: $P=z(...)+y(...)+(some constants)$

I knoe its quite easy but this is just an example what I want to do in real is a polynomial with 60 terms in it so i would like to know the procedure for doing this.

  • $\begingroup$ tried Collect? $\endgroup$ – kglr Jul 11 '19 at 9:14
  • $\begingroup$ Your example is bad since in fact the polynomial is 3 + 17 x y + 106 x z, which remains the same after vars = Variables[P];Collect[P, Rest[vars], Factor] $\endgroup$ – user18792 Jul 11 '19 at 9:17
  • $\begingroup$ @ user18792 the answer to this example is straightforward and supposed to be $P=z(3^4x+5^2x)+y(x+2^4x)+3$ $\endgroup$ – Jason Jul 11 '19 at 9:20
  • $\begingroup$ @ kglr Thanks it worked $\endgroup$ – Jason Jul 11 '19 at 11:51

You can use Collect:

poly = Inactivate[y x + 2^4 x y + 3 + 5^2 x z + 3^4 z x, Power]
Collect[poly, {y, z}]

enter image description here

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