diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/amount.cc | 52 |
1 files changed, 39 insertions, 13 deletions
diff --git a/src/amount.cc b/src/amount.cc index 1cba92f8..9b7c3676 100644 --- a/src/amount.cc +++ b/src/amount.cc @@ -47,6 +47,8 @@ static mpz_t temp; static mpq_t tempq; static mpfr_t tempf; static mpfr_t tempfb; +static mpfr_t tempfnum; +static mpfr_t tempfden; #endif struct amount_t::bigint_t : public supports_flags<> @@ -111,7 +113,7 @@ bool amount_t::is_initialized = false; namespace { void stream_out_mpq(std::ostream& out, mpq_t quant, - amount_t::precision_t prec, + amount_t::precision_t precision, int zeros_prec = -1, const optional<commodity_t&>& comm = none) { @@ -125,17 +127,39 @@ namespace { // Convert the rational number to a floating-point, extending the // floating-point to a large enough size to get a precise answer. - const std::size_t bits = (mpz_sizeinbase(mpq_numref(quant), 2) + - mpz_sizeinbase(mpq_denref(quant), 2)); - mpfr_set_prec(tempfb, bits + amount_t::extend_by_digits*8); - mpfr_set_q(tempfb, quant, GMP_RNDN); - if (mpfr_asprintf(&buf, "%.*Rf", prec, tempfb) < 0) + mp_prec_t num_prec = mpz_sizeinbase(mpq_numref(quant), 2); + num_prec += amount_t::extend_by_digits*64; + if (num_prec < MPFR_PREC_MIN) + num_prec = MPFR_PREC_MIN; + DEBUG("amount.convert", "num prec = " << num_prec); + + mpfr_set_prec(tempfnum, num_prec); + mpfr_set_z(tempfnum, mpq_numref(quant), GMP_RNDN); + + mp_prec_t den_prec = mpz_sizeinbase(mpq_denref(quant), 2); + den_prec += amount_t::extend_by_digits*64; + if (den_prec < MPFR_PREC_MIN) + den_prec = MPFR_PREC_MIN; + DEBUG("amount.convert", "den prec = " << den_prec); + + mpfr_set_prec(tempfden, den_prec); + mpfr_set_z(tempfden, mpq_denref(quant), GMP_RNDN); + + mpfr_set_prec(tempfb, num_prec + den_prec); + mpfr_div(tempfb, tempfnum, tempfden, GMP_RNDN); + + char bigbuf[4096]; + mpfr_sprintf(bigbuf, "%.RNf", tempfb); + DEBUG("amount.convert", "num/den = " << bigbuf); + + if (mpfr_asprintf(&buf, "%.*RNf", precision, tempfb) < 0) throw_(amount_error, _("Cannot output amount to a floating-point representation")); - DEBUG("amount.convert", - "mpfr_print = " << buf << " (precision " << prec << ")"); + DEBUG("amount.convert", "mpfr_print = " << buf + << " (precision " << precision + << ", zeros_prec " << zeros_prec << ")"); if (zeros_prec >= 0) { string::size_type index = std::strlen(buf); @@ -211,6 +235,8 @@ void amount_t::initialize() mpq_init(tempq); mpfr_init(tempf); mpfr_init(tempfb); + mpfr_init(tempfnum); + mpfr_init(tempfden); commodity_pool_t::current_pool.reset(new commodity_pool_t); @@ -238,6 +264,8 @@ void amount_t::shutdown() mpq_clear(tempq); mpfr_clear(tempf); mpfr_clear(tempfb); + mpfr_clear(tempfnum); + mpfr_clear(tempfden); commodity_pool_t::current_pool.reset(); @@ -556,12 +584,10 @@ amount_t::precision_t amount_t::display_precision() const commodity_t& comm(commodity()); - if (! comm || keep_precision()) - return quantity->prec; - else if (comm.precision() != quantity->prec) + if (comm && ! keep_precision()) return comm.precision(); else - return quantity->prec; + return comm ? std::max(quantity->prec, comm.precision()) : quantity->prec; } void amount_t::in_place_negate() @@ -643,7 +669,7 @@ void amount_t::in_place_floor() _dup(); std::ostringstream out; - stream_out_mpq(out, MP(quantity), 0); + stream_out_mpq(out, MP(quantity), precision_t(0)); mpq_set_str(MP(quantity), out.str().c_str(), 10); } |