Hi all, I suggest adding a public mpn function
mpn_tdiv_q(mp_ptr, mp_srcptr, mp_size_t, mp_srcptr, mp_size_t) that computes a correctly rounded truncated quotient, disallowing aliasing. This could simply be implemented using TMP_ALLOC_LIMBS + mpn_div_q (possibly with a special case for mpn_divrem_1). Such a function would be very useful for dividing floating-point numbers, among other things. Currently, if one works with mpn data, the options are: * mpn_div_q, but this is undocumented and requires the user to handle temporary space -- see the discussion 4 years ago: https://gmplib.org/list-archives/gmp-devel/2010-September/001651.html * mpn_tdiv_qr, but mpn_div_q is vastly faster for generic divisions when one does not need the remainder * mpz_tdiv_q, but this requires moving data in and out of mpz variables An mpn_tdiv_q function would provide a stable and obvious division interface without either of those drawbacks. It could be added independently of other potential changes such as changing the amount of temp space required by mpn_div_q (or removing this parameter entirely, effectively making mpn_div_q/mpn_tdiv_q aliases for the same thing). The overhead of the extra temporary allocation (sometimes avoidable with mpn_div_q as one can reuse memory intended for something else) would usually be minor compared to calling mpn_tdiv_qr or mpz_tdiv_q. The interface would also happen to be compatible with a certain GMP fork, which is convenient for third party software. Best wishes, Fredrik _______________________________________________ gmp-devel mailing list gmp-devel@gmplib.org https://gmplib.org/mailman/listinfo/gmp-devel
