Dear all,

I am using the function to_polynomial to produce a polynomial from a expression,

it seems that to_polynomial does not return a polynomial in some cases,

as illustrated in the following example, note that it works well on expression e2,

while it does nothing on e3 (e3=e2^2), and does not return a polynomial.

#include "ginac/GiNaC.h"

using namespace GiNaC;

using namespace std;

int main() {

symbol x("x"), y("y");

auto e1 = x+y;

auto e2 = e1+1/e1+pow(e1,4);

auto e3 = pow(e2, 2);

exmap mp2;

ex p2 = e2.to_polynomial(mp2);

cout << " = " << p2 << "\n with " << mp2 << endl;

//= y+symbol4+x+(y+x)^4

// with {symbol4==(y+x)^(-1)}

exmap mp3;

ex p3 = e3.to_polynomial(mp3);

cout << " = " << p3 << "\n with " << mp3 << endl;

//= (y+(y+x)^(-1)+x+(y+x)^4)^2

//with {}

return 0;

}

Best regards!

Feng