X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fnumeric.cpp;h=e621607a730cabb8878cd5b5cf7d2c0b0dd71b54;hp=ef4e3e929ce5732f854bfae80d3f72f9f55e2b34;hb=c86cff51ac5a42f86387ef7bc767f1274137350b;hpb=bfb395b4e24e659fc46abc2d2ad4305168d1c6f2 diff --git a/ginac/numeric.cpp b/ginac/numeric.cpp index ef4e3e92..e621607a 100644 --- a/ginac/numeric.cpp +++ b/ginac/numeric.cpp @@ -29,20 +29,13 @@ #include #include #include - -#if defined(HAVE_SSTREAM) #include -#elif defined(HAVE_STRSTREAM) -#include -#else -#error Need either sstream or strstream -#endif #include "numeric.h" #include "ex.h" #include "print.h" #include "archive.h" -#include "debugmsg.h" +#include "tostring.h" #include "utils.h" // CLN should pollute the global namespace as little as possible. Hence, we @@ -69,14 +62,12 @@ namespace GiNaC { GINAC_IMPLEMENT_REGISTERED_CLASS(numeric, basic) ////////// -// default ctor, dtor, copy ctor assignment -// operator and helpers +// default ctor, dtor, copy ctor, assignment operator and helpers ////////// /** default ctor. Numerically it initializes to an integer zero. */ numeric::numeric() : basic(TINFO_numeric) { - debugmsg("numeric default ctor", LOGLEVEL_CONSTRUCT); value = cln::cl_I(0); setflag(status_flags::evaluated | status_flags::expanded); } @@ -97,7 +88,6 @@ DEFAULT_DESTROY(numeric) numeric::numeric(int i) : basic(TINFO_numeric) { - debugmsg("numeric ctor from int",LOGLEVEL_CONSTRUCT); // Not the whole int-range is available if we don't cast to long // first. This is due to the behaviour of the cl_I-ctor, which // emphasizes efficiency. However, if the integer is small enough, @@ -113,7 +103,6 @@ numeric::numeric(int i) : basic(TINFO_numeric) numeric::numeric(unsigned int i) : basic(TINFO_numeric) { - debugmsg("numeric ctor from uint",LOGLEVEL_CONSTRUCT); // Not the whole uint-range is available if we don't cast to ulong // first. This is due to the behaviour of the cl_I-ctor, which // emphasizes efficiency. However, if the integer is small enough, @@ -129,7 +118,6 @@ numeric::numeric(unsigned int i) : basic(TINFO_numeric) numeric::numeric(long i) : basic(TINFO_numeric) { - debugmsg("numeric ctor from long",LOGLEVEL_CONSTRUCT); value = cln::cl_I(i); setflag(status_flags::evaluated | status_flags::expanded); } @@ -137,7 +125,6 @@ numeric::numeric(long i) : basic(TINFO_numeric) numeric::numeric(unsigned long i) : basic(TINFO_numeric) { - debugmsg("numeric ctor from ulong",LOGLEVEL_CONSTRUCT); value = cln::cl_I(i); setflag(status_flags::evaluated | status_flags::expanded); } @@ -147,7 +134,6 @@ numeric::numeric(unsigned long i) : basic(TINFO_numeric) * @exception overflow_error (division by zero) */ numeric::numeric(long numer, long denom) : basic(TINFO_numeric) { - debugmsg("numeric ctor from long/long",LOGLEVEL_CONSTRUCT); if (!denom) throw std::overflow_error("division by zero"); value = cln::cl_I(numer) / cln::cl_I(denom); @@ -157,7 +143,6 @@ numeric::numeric(long numer, long denom) : basic(TINFO_numeric) numeric::numeric(double d) : basic(TINFO_numeric) { - debugmsg("numeric ctor from double",LOGLEVEL_CONSTRUCT); // We really want to explicitly use the type cl_LF instead of the // more general cl_F, since that would give us a cl_DF only which // will not be promoted to cl_LF if overflow occurs: @@ -170,40 +155,47 @@ numeric::numeric(double d) : basic(TINFO_numeric) * notation like "2+5*I". */ numeric::numeric(const char *s) : basic(TINFO_numeric) { - debugmsg("numeric ctor from string",LOGLEVEL_CONSTRUCT); cln::cl_N ctorval = 0; // parse complex numbers (functional but not completely safe, unfortunately // std::string does not understand regexpese): // ss should represent a simple sum like 2+5*I - std::string ss(s); - // make it safe by adding explicit sign + std::string ss = s; + std::string::size_type delim; + + // make this implementation safe by adding explicit sign if (ss.at(0) != '+' && ss.at(0) != '-' && ss.at(0) != '#') ss = '+' + ss; - std::string::size_type delim; + + // We use 'E' as exponent marker in the output, but some people insist on + // writing 'e' at input, so let's substitute them right at the beginning: + while ((delim = ss.find("e"))!=std::string::npos) + ss.replace(delim,1,"E"); + + // main parser loop: do { // chop ss into terms from left to right std::string term; bool imaginary = false; delim = ss.find_first_of(std::string("+-"),1); // Do we have an exponent marker like "31.415E-1"? If so, hop on! - if ((delim != std::string::npos) && (ss.at(delim-1) == 'E')) + if (delim!=std::string::npos && ss.at(delim-1)=='E') delim = ss.find_first_of(std::string("+-"),delim+1); term = ss.substr(0,delim); - if (delim != std::string::npos) + if (delim!=std::string::npos) ss = ss.substr(delim); // is the term imaginary? - if (term.find("I") != std::string::npos) { + if (term.find("I")!=std::string::npos) { // erase 'I': - term = term.replace(term.find("I"),1,""); + term.erase(term.find("I"),1); // erase '*': - if (term.find("*") != std::string::npos) - term = term.replace(term.find("*"),1,""); + if (term.find("*")!=std::string::npos) + term.erase(term.find("*"),1); // correct for trivial +/-I without explicit factor on I: - if (term.size() == 1) - term += "1"; + if (term.size()==1) + term += '1'; imaginary = true; } - if (term.find(".") != std::string::npos) { + if (term.find('.')!=std::string::npos || term.find('E')!=std::string::npos) { // CLN's short type cl_SF is not very useful within the GiNaC // framework where we are mainly interested in the arbitrary // precision type cl_LF. Hence we go straight to the construction @@ -214,33 +206,25 @@ numeric::numeric(const char *s) : basic(TINFO_numeric) // 31.4E-1 --> 31.4e-1_ // and s on. // No exponent marker? Let's add a trivial one. - if (term.find("E") == std::string::npos) + if (term.find("E")==std::string::npos) term += "E0"; // E to lower case term = term.replace(term.find("E"),1,"e"); // append _ to term -#if defined(HAVE_SSTREAM) - std::ostringstream buf; - buf << unsigned(Digits) << std::ends; - term += "_" + buf.str(); -#else - char buf[14]; - std::ostrstream(buf,sizeof(buf)) << unsigned(Digits) << std::ends; - term += "_" + std::string(buf); -#endif + term += "_" + ToString((unsigned)Digits); // construct float using cln::cl_F(const char *) ctor. if (imaginary) ctorval = ctorval + cln::complex(cln::cl_I(0),cln::cl_F(term.c_str())); else ctorval = ctorval + cln::cl_F(term.c_str()); } else { - // not a floating point number... + // this is not a floating point number... if (imaginary) ctorval = ctorval + cln::complex(cln::cl_I(0),cln::cl_R(term.c_str())); else ctorval = ctorval + cln::cl_R(term.c_str()); } - } while(delim != std::string::npos); + } while (delim != std::string::npos); value = ctorval; setflag(status_flags::evaluated | status_flags::expanded); } @@ -250,7 +234,6 @@ numeric::numeric(const char *s) : basic(TINFO_numeric) * only. */ numeric::numeric(const cln::cl_N &z) : basic(TINFO_numeric) { - debugmsg("numeric ctor from cl_N", LOGLEVEL_CONSTRUCT); value = z; setflag(status_flags::evaluated | status_flags::expanded); } @@ -261,17 +244,12 @@ numeric::numeric(const cln::cl_N &z) : basic(TINFO_numeric) numeric::numeric(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst) { - debugmsg("numeric ctor from archive_node", LOGLEVEL_CONSTRUCT); cln::cl_N ctorval = 0; // Read number as string std::string str; if (n.find_string("number", str)) { -#ifdef HAVE_SSTREAM std::istringstream s(str); -#else - std::istrstream s(str.c_str(), str.size() + 1); -#endif cln::cl_idecoded_float re, im; char c; s.get(c); @@ -301,12 +279,7 @@ void numeric::archive(archive_node &n) const inherited::archive(n); // Write number as string -#ifdef HAVE_SSTREAM std::ostringstream s; -#else - char buf[1024]; - std::ostrstream s(buf, 1024); -#endif if (this->is_crational()) s << cln::the(value); else { @@ -324,19 +297,13 @@ void numeric::archive(archive_node &n) const s << im.sign << " " << im.mantissa << " " << im.exponent; } } -#ifdef HAVE_SSTREAM n.add_string("number", s.str()); -#else - s << ends; - std::string str(buf); - n.add_string("number", str); -#endif } DEFAULT_UNARCHIVE(numeric) ////////// -// functions overriding virtual functions from bases classes +// functions overriding virtual functions from base classes ////////// /** Helper function to print a real number in a nicer way than is CLN's @@ -346,20 +313,28 @@ DEFAULT_UNARCHIVE(numeric) * want to visibly distinguish from cl_LF. * * @see numeric::print() */ -static void print_real_number(std::ostream &os, const cln::cl_R &num) +static void print_real_number(const print_context & c, const cln::cl_R &x) { cln::cl_print_flags ourflags; - if (cln::instanceof(num, cln::cl_RA_ring)) { - // case 1: integer or rational, nothing special to do: - cln::print_real(os, ourflags, num); + if (cln::instanceof(x, cln::cl_RA_ring)) { + // case 1: integer or rational + if (cln::instanceof(x, cln::cl_I_ring) || + !is_a(c)) { + cln::print_real(c.s, ourflags, x); + } else { // rational output in LaTeX context + c.s << "\\frac{"; + cln::print_real(c.s, ourflags, cln::numerator(cln::the(x))); + c.s << "}{"; + cln::print_real(c.s, ourflags, cln::denominator(cln::the(x))); + c.s << '}'; + } } else { // case 2: float // make CLN believe this number has default_float_format, so it prints // 'E' as exponent marker instead of 'L': - ourflags.default_float_format = cln::float_format(cln::the(num)); - cln::print_real(os, ourflags, num); + ourflags.default_float_format = cln::float_format(cln::the(x)); + cln::print_real(c.s, ourflags, x); } - return; } /** This method adds to the output so it blends more consistently together @@ -368,41 +343,39 @@ static void print_real_number(std::ostream &os, const cln::cl_R &num) * @see print_real_number() */ void numeric::print(const print_context & c, unsigned level) const { - debugmsg("numeric print", LOGLEVEL_PRINT); - - if (is_of_type(c, print_tree)) { + if (is_a(c)) { c.s << std::string(level, ' ') << cln::the(value) << " (" << class_name() << ")" << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec << std::endl; - } else if (is_of_type(c, print_csrc)) { + } else if (is_a(c)) { std::ios::fmtflags oldflags = c.s.flags(); c.s.setf(std::ios::scientific); if (this->is_rational() && !this->is_integer()) { - if (compare(_num0()) > 0) { + if (compare(_num0) > 0) { c.s << "("; - if (is_of_type(c, print_csrc_cl_N)) + if (is_a(c)) c.s << "cln::cl_F(\"" << numer().evalf() << "\")"; else c.s << numer().to_double(); } else { c.s << "-("; - if (is_of_type(c, print_csrc_cl_N)) + if (is_a(c)) c.s << "cln::cl_F(\"" << -numer().evalf() << "\")"; else c.s << -numer().to_double(); } c.s << "/"; - if (is_of_type(c, print_csrc_cl_N)) + if (is_a(c)) c.s << "cln::cl_F(\"" << denom().evalf() << "\")"; else c.s << denom().to_double(); c.s << ")"; } else { - if (is_of_type(c, print_csrc_cl_N)) + if (is_a(c)) c.s << "cln::cl_F(\"" << evalf() << "\")"; else c.s << to_double(); @@ -410,30 +383,32 @@ void numeric::print(const print_context & c, unsigned level) const c.s.flags(oldflags); } else { - const std::string par_open = is_of_type(c, print_latex) ? "{(" : "("; - const std::string par_close = is_of_type(c, print_latex) ? ")}" : ")"; - const std::string imag_sym = is_of_type(c, print_latex) ? "i" : "I"; - const std::string mul_sym = is_of_type(c, print_latex) ? " " : "*"; + const std::string par_open = is_a(c) ? "{(" : "("; + const std::string par_close = is_a(c) ? ")}" : ")"; + const std::string imag_sym = is_a(c) ? "i" : "I"; + const std::string mul_sym = is_a(c) ? " " : "*"; const cln::cl_R r = cln::realpart(cln::the(value)); const cln::cl_R i = cln::imagpart(cln::the(value)); + if (is_a(c)) + c.s << class_name() << "('"; if (cln::zerop(i)) { // case 1, real: x or -x - if ((precedence <= level) && (!this->is_nonneg_integer())) { + if ((precedence() <= level) && (!this->is_nonneg_integer())) { c.s << par_open; - print_real_number(c.s, r); + print_real_number(c, r); c.s << par_close; } else { - print_real_number(c.s, r); + print_real_number(c, r); } } else { if (cln::zerop(r)) { // case 2, imaginary: y*I or -y*I - if ((precedence <= level) && (i < 0)) { + if ((precedence() <= level) && (i < 0)) { if (i == -1) { c.s << par_open+imag_sym+par_close; } else { c.s << par_open; - print_real_number(c.s, i); + print_real_number(c, i); c.s << mul_sym+imag_sym+par_close; } } else { @@ -443,21 +418,21 @@ void numeric::print(const print_context & c, unsigned level) const if (i == -1) { c.s << "-" << imag_sym; } else { - print_real_number(c.s, i); + print_real_number(c, i); c.s << mul_sym+imag_sym; } } } } else { // case 3, complex: x+y*I or x-y*I or -x+y*I or -x-y*I - if (precedence <= level) + if (precedence() <= level) c.s << par_open; - print_real_number(c.s, r); + print_real_number(c, r); if (i < 0) { if (i == -1) { c.s << "-"+imag_sym; } else { - print_real_number(c.s, i); + print_real_number(c, i); c.s << mul_sym+imag_sym; } } else { @@ -465,14 +440,16 @@ void numeric::print(const print_context & c, unsigned level) const c.s << "+"+imag_sym; } else { c.s << "+"; - print_real_number(c.s, i); + print_real_number(c, i); c.s << mul_sym+imag_sym; } } - if (precedence <= level) + if (precedence() <= level) c.s << par_close; } } + if (is_a(c)) + c.s << "')"; } } @@ -529,9 +506,9 @@ bool numeric::info(unsigned inf) const * sign as a multiplicative factor. */ bool numeric::has(const ex &other) const { - if (!is_exactly_of_type(*other.bp, numeric)) + if (!is_ex_exactly_of_type(other, numeric)) return false; - const numeric &o = static_cast(const_cast(*other.bp)); + const numeric &o = ex_to(other); if (this->is_equal(o) || this->is_equal(-o)) return true; if (o.imag().is_zero()) // e.g. scan for 3 in -3*I @@ -575,8 +552,8 @@ ex numeric::evalf(int level) const int numeric::compare_same_type(const basic &other) const { - GINAC_ASSERT(is_exactly_of_type(other, numeric)); - const numeric &o = static_cast(const_cast(other)); + GINAC_ASSERT(is_exactly_a(other)); + const numeric &o = static_cast(other); return this->compare(o); } @@ -584,10 +561,10 @@ int numeric::compare_same_type(const basic &other) const bool numeric::is_equal_same_type(const basic &other) const { - GINAC_ASSERT(is_exactly_of_type(other,numeric)); - const numeric *o = static_cast(&other); + GINAC_ASSERT(is_exactly_a(other)); + const numeric &o = static_cast(other); - return this->is_equal(*o); + return this->is_equal(o); } @@ -618,10 +595,9 @@ unsigned numeric::calchash(void) const const numeric numeric::add(const numeric &other) const { // Efficiency shortcut: trap the neutral element by pointer. - static const numeric * _num0p = &_num0(); - if (this==_num0p) + if (this==_num0_p) return other; - else if (&other==_num0p) + else if (&other==_num0_p) return *this; return numeric(cln::the(value)+cln::the(other.value)); @@ -641,10 +617,9 @@ const numeric numeric::sub(const numeric &other) const const numeric numeric::mul(const numeric &other) const { // Efficiency shortcut: trap the neutral element by pointer. - static const numeric * _num1p = &_num1(); - if (this==_num1p) + if (this==_num1_p) return other; - else if (&other==_num1p) + else if (&other==_num1_p) return *this; return numeric(cln::the(value)*cln::the(other.value)); @@ -668,8 +643,7 @@ const numeric numeric::div(const numeric &other) const const numeric numeric::power(const numeric &other) const { // Efficiency shortcut: trap the neutral exponent by pointer. - static const numeric * _num1p = &_num1(); - if (&other==_num1p) + if (&other==_num1_p) return *this; if (cln::zerop(cln::the(value))) { @@ -680,7 +654,7 @@ const numeric numeric::power(const numeric &other) const else if (cln::minusp(cln::realpart(cln::the(other.value)))) throw std::overflow_error("numeric::eval(): division by zero"); else - return _num0(); + return _num0; } return numeric(cln::expt(cln::the(value),cln::the(other.value))); } @@ -689,10 +663,9 @@ const numeric numeric::power(const numeric &other) const const numeric &numeric::add_dyn(const numeric &other) const { // Efficiency shortcut: trap the neutral element by pointer. - static const numeric * _num0p = &_num0(); - if (this==_num0p) + if (this==_num0_p) return other; - else if (&other==_num0p) + else if (&other==_num0_p) return *this; return static_cast((new numeric(cln::the(value)+cln::the(other.value)))-> @@ -710,10 +683,9 @@ const numeric &numeric::sub_dyn(const numeric &other) const const numeric &numeric::mul_dyn(const numeric &other) const { // Efficiency shortcut: trap the neutral element by pointer. - static const numeric * _num1p = &_num1(); - if (this==_num1p) + if (this==_num1_p) return other; - else if (&other==_num1p) + else if (&other==_num1_p) return *this; return static_cast((new numeric(cln::the(value)*cln::the(other.value)))-> @@ -733,8 +705,7 @@ const numeric &numeric::div_dyn(const numeric &other) const const numeric &numeric::power_dyn(const numeric &other) const { // Efficiency shortcut: trap the neutral exponent by pointer. - static const numeric * _num1p=&_num1(); - if (&other==_num1p) + if (&other==_num1_p) return *this; if (cln::zerop(cln::the(value))) { @@ -745,7 +716,7 @@ const numeric &numeric::power_dyn(const numeric &other) const else if (cln::minusp(cln::realpart(cln::the(other.value)))) throw std::overflow_error("numeric::eval(): division by zero"); else - return _num0(); + return _num0; } return static_cast((new numeric(cln::expt(cln::the(value),cln::the(other.value))))-> setflag(status_flags::dynallocated)); @@ -1112,7 +1083,7 @@ const numeric numeric::numer(void) const const numeric numeric::denom(void) const { if (this->is_integer()) - return _num1(); + return _num1; if (cln::instanceof(value, cln::cl_RA_ring)) return numeric(cln::denominator(cln::the(value))); @@ -1121,7 +1092,7 @@ const numeric numeric::denom(void) const const cln::cl_RA r = cln::the(cln::realpart(cln::the(value))); const cln::cl_RA i = cln::the(cln::imagpart(cln::the(value))); if (cln::instanceof(r, cln::cl_I_ring) && cln::instanceof(i, cln::cl_I_ring)) - return _num1(); + return _num1; if (cln::instanceof(r, cln::cl_I_ring) && cln::instanceof(i, cln::cl_RA_ring)) return numeric(cln::denominator(i)); if (cln::instanceof(r, cln::cl_RA_ring) && cln::instanceof(i, cln::cl_I_ring)) @@ -1130,7 +1101,7 @@ const numeric numeric::denom(void) const return numeric(cln::lcm(cln::denominator(r), cln::denominator(i))); } // at least one float encountered - return _num1(); + return _num1; } @@ -1148,15 +1119,6 @@ int numeric::int_length(void) const return 0; } - -////////// -// static member variables -////////// - -// protected - -unsigned numeric::precedence = 30; - ////////// // global constants ////////// @@ -1243,7 +1205,7 @@ const numeric atan(const numeric &x) { if (!x.is_real() && x.real().is_zero() && - abs(x.imag()).is_equal(_num1())) + abs(x.imag()).is_equal(_num1)) throw pole_error("atan(): logarithmic pole",0); return cln::atan(x.to_cl_N()); } @@ -1394,7 +1356,7 @@ static cln::cl_N Li2_projection(const cln::cl_N &x, const numeric Li2(const numeric &x) { if (x.is_zero()) - return _num0(); + return _num0; // what is the desired float format? // first guess: default format @@ -1433,10 +1395,7 @@ const numeric zeta(const numeric &x) if (cln::zerop(x.to_cl_N()-aux)) return cln::zeta(aux); } - std::clog << "zeta(" << x - << "): Does anybody know a good way to calculate this numerically?" - << std::endl; - return numeric(0); + throw dunno(); } @@ -1444,17 +1403,11 @@ const numeric zeta(const numeric &x) * This is only a stub! */ const numeric lgamma(const numeric &x) { - std::clog << "lgamma(" << x - << "): Does anybody know a good way to calculate this numerically?" - << std::endl; - return numeric(0); + throw dunno(); } const numeric tgamma(const numeric &x) { - std::clog << "tgamma(" << x - << "): Does anybody know a good way to calculate this numerically?" - << std::endl; - return numeric(0); + throw dunno(); } @@ -1462,10 +1415,7 @@ const numeric tgamma(const numeric &x) * This is only a stub! */ const numeric psi(const numeric &x) { - std::clog << "psi(" << x - << "): Does anybody know a good way to calculate this numerically?" - << std::endl; - return numeric(0); + throw dunno(); } @@ -1473,10 +1423,7 @@ const numeric psi(const numeric &x) * This is only a stub! */ const numeric psi(const numeric &n, const numeric &x) { - std::clog << "psi(" << n << "," << x - << "): Does anybody know a good way to calculate this numerically?" - << std::endl; - return numeric(0); + throw dunno(); } @@ -1500,8 +1447,8 @@ const numeric factorial(const numeric &n) * @exception range_error (argument must be integer >= -1) */ const numeric doublefactorial(const numeric &n) { - if (n.is_equal(_num_1())) - return _num1(); + if (n.is_equal(_num_1)) + return _num1; if (!n.is_nonneg_integer()) throw std::range_error("numeric::doublefactorial(): argument must be integer >= -1"); @@ -1518,12 +1465,12 @@ const numeric binomial(const numeric &n, const numeric &k) { if (n.is_integer() && k.is_integer()) { if (n.is_nonneg_integer()) { - if (k.compare(n)!=1 && k.compare(_num0())!=-1) + if (k.compare(n)!=1 && k.compare(_num0)!=-1) return numeric(cln::binomial(n.to_int(),k.to_int())); else - return _num0(); + return _num0; } else { - return _num_1().power(k)*binomial(k-n-_num1(),k); + return _num_1.power(k)*binomial(k-n-_num1,k); } } @@ -1541,7 +1488,7 @@ const numeric bernoulli(const numeric &nn) { if (!nn.is_integer() || nn.is_negative()) throw std::range_error("numeric::bernoulli(): argument must be integer >= 0"); - + // Method: // // The Bernoulli numbers are rational numbers that may be computed using @@ -1565,46 +1512,49 @@ const numeric bernoulli(const numeric &nn) // But if somebody works with the n'th Bernoulli number she is likely to // also need all previous Bernoulli numbers. So we need a complete remember // table and above divide and conquer algorithm is not suited to build one - // up. The code below is adapted from Pari's function bernvec(). + // up. The formula below accomplishes this. It is a modification of the + // defining formula above but the computation of the binomial coefficients + // is carried along in an inline fashion. It also honors the fact that + // B_n is zero when n is odd and greater than 1. // // (There is an interesting relation with the tangent polynomials described - // in `Concrete Mathematics', which leads to a program twice as fast as our - // implementation below, but it requires storing one such polynomial in + // in `Concrete Mathematics', which leads to a program a little faster as + // our implementation below, but it requires storing one such polynomial in // addition to the remember table. This doubles the memory footprint so // we don't use it.) - + + const unsigned n = nn.to_int(); + // the special cases not covered by the algorithm below - if (nn.is_equal(_num1())) - return _num_1_2(); - if (nn.is_odd()) - return _num0(); - + if (n & 1) + return (n==1) ? _num_1_2 : _num0; + if (!n) + return _num1; + // store nonvanishing Bernoulli numbers here static std::vector< cln::cl_RA > results; - static int highest_result = 0; - // algorithm not applicable to B(0), so just store it - if (results.size()==0) - results.push_back(cln::cl_RA(1)); - - int n = nn.to_long(); - for (int i=highest_result; i0; --j) { - B = cln::cl_I(n*m) * (B+results[j]) / (d1*d2); - n += 4; - m += 2; - d1 -= 1; - d2 -= 2; + static unsigned next_r = 0; + + // algorithm not applicable to B(2), so just store it + if (!next_r) { + results.push_back(cln::recip(cln::cl_RA(6))); + next_r = 4; + } + for (unsigned p=next_r; p<=n; p+=2) { + cln::cl_I c = 1; + cln::cl_RA b = cln::cl_RA(1-p)/2; + const unsigned p3 = p+3; + const unsigned p2 = p+2; + const unsigned pm = p-2; + unsigned i, k; + for (i=2, k=0; i <= pm; i += 2, k++) { + c = cln::exquo(c * ((p3 - i)*(p2 - i)), (i - 1)*i); + b = b + c * results[k]; } - B = (1 - ((B+1)/(2*i+3))) / (cln::cl_I(1)<<(2*i+2)); - results.push_back(B); - ++highest_result; + results.push_back(-b / (p+1)); + next_r += 2; } - return results[n/2]; + return results[n/2 - 1]; } @@ -1635,7 +1585,7 @@ const numeric fibonacci(const numeric &n) // hence // F(2n+2) = F(n+1)*(2*F(n) + F(n+1)) if (n.is_zero()) - return _num0(); + return _num0; if (n.is_negative()) if (n.is_even()) return -fibonacci(-n); @@ -1687,7 +1637,7 @@ const numeric mod(const numeric &a, const numeric &b) return cln::mod(cln::the(a.to_cl_N()), cln::the(b.to_cl_N())); else - return _num0(); + return _num0; } @@ -1702,7 +1652,7 @@ const numeric smod(const numeric &a, const numeric &b) return cln::mod(cln::the(a.to_cl_N()) + b2, cln::the(b.to_cl_N())) - b2; } else - return _num0(); + return _num0; } @@ -1718,7 +1668,7 @@ const numeric irem(const numeric &a, const numeric &b) return cln::rem(cln::the(a.to_cl_N()), cln::the(b.to_cl_N())); else - return _num0(); + return _num0; } @@ -1737,8 +1687,8 @@ const numeric irem(const numeric &a, const numeric &b, numeric &q) q = rem_quo.quotient; return rem_quo.remainder; } else { - q = _num0(); - return _num0(); + q = _num0; + return _num0; } } @@ -1753,7 +1703,7 @@ const numeric iquo(const numeric &a, const numeric &b) return cln::truncate1(cln::the(a.to_cl_N()), cln::the(b.to_cl_N())); else - return _num0(); + return _num0; } @@ -1771,8 +1721,8 @@ const numeric iquo(const numeric &a, const numeric &b, numeric &r) r = rem_quo.remainder; return rem_quo.quotient; } else { - r = _num0(); - return _num0(); + r = _num0; + return _num0; } } @@ -1787,7 +1737,7 @@ const numeric gcd(const numeric &a, const numeric &b) return cln::gcd(cln::the(a.to_cl_N()), cln::the(b.to_cl_N())); else - return _num1(); + return _num1; } @@ -1827,7 +1777,7 @@ const numeric isqrt(const numeric &x) cln::isqrt(cln::the(x.to_cl_N()), &root); return root; } else - return _num0(); + return _num0; } @@ -1886,7 +1836,6 @@ _numeric_digits::operator long() /** Append global Digits object to ostream. */ void _numeric_digits::print(std::ostream &os) const { - debugmsg("_numeric_digits print", LOGLEVEL_PRINT); os << digits; }