void arb_poly_revert_series_lagrange_fast(arb_poly_t Qinv, const arb_poly_t Q, long n, long prec) { long Qlen = Q->length; if (Qlen < 2 || !arb_is_zero(Q->coeffs) || arb_contains_zero(Q->coeffs + 1)) { printf("Exception (arb_poly_revert_series_lagrange_fast). Input \n" "must have zero constant term and nonzero coefficient of x^1.\n"); abort(); } if (Qinv != Q) { arb_poly_fit_length(Qinv, n); _arb_poly_revert_series_lagrange_fast(Qinv->coeffs, Q->coeffs, Qlen, n, prec); } else { arb_poly_t t; arb_poly_init2(t, n); _arb_poly_revert_series_lagrange_fast(t->coeffs, Q->coeffs, Qlen, n, prec); arb_poly_swap(Qinv, t); arb_poly_clear(t); } _arb_poly_set_length(Qinv, n); _arb_poly_normalise(Qinv); }
void _arb_poly_revert_series(arb_ptr Qinv, arb_srcptr Q, slong Qlen, slong n, slong prec) { _arb_poly_revert_series_lagrange_fast(Qinv, Q, Qlen, n, prec); }