3 * Implementation of GiNaC's constant types and some special constants. */
6 * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
36 GINAC_IMPLEMENT_REGISTERED_CLASS(constant, basic)
39 // default ctor, dtor, copy ctor, assignment operator and helpers
44 constant::constant() : basic(TINFO_constant), ef(0), number(0), serial(next_serial++) {}
48 /** For use by copy ctor and assignment operator. */
49 void constant::copy(const constant & other)
51 inherited::copy(other);
53 TeX_name = other.TeX_name;
54 serial = other.serial;
56 if (other.number != 0)
57 number = new numeric(*other.number);
62 void constant::destroy(bool call_parent)
66 inherited::destroy(call_parent);
75 constant::constant(const std::string & initname, evalffunctype efun, const std::string & texname)
76 : basic(TINFO_constant), name(initname), ef(efun), number(0), serial(next_serial++)
79 TeX_name = "\\mbox{" + name + "}";
82 setflag(status_flags::evaluated | status_flags::expanded);
85 constant::constant(const std::string & initname, const numeric & initnumber, const std::string & texname)
86 : basic(TINFO_constant), name(initname), ef(0), number(new numeric(initnumber)), serial(next_serial++)
89 TeX_name = "\\mbox{" + name + "}";
92 setflag(status_flags::evaluated | status_flags::expanded);
99 constant::constant(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst) {}
101 ex constant::unarchive(const archive_node &n, const lst &sym_lst)
103 // Find constant by name (!! this is bad: 'twould be better if there
104 // was a list of all global constants that we could search)
106 if (n.find_string("name", s)) {
109 else if (s == Catalan.name)
111 else if (s == Euler.name)
114 throw (std::runtime_error("unknown constant '" + s + "' in archive"));
116 throw (std::runtime_error("unnamed constant in archive"));
119 void constant::archive(archive_node &n) const
121 inherited::archive(n);
122 n.add_string("name", name);
126 // functions overriding virtual functions from base classes
131 void constant::print(const print_context & c, unsigned level) const
133 if (is_a<print_tree>(c)) {
134 c.s << std::string(level, ' ') << name << " (" << class_name() << ")"
135 << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
137 } else if (is_a<print_latex>(c))
143 int constant::degree(const ex & s) const
145 return is_equal(ex_to<basic>(s)) ? 1 : 0;
148 int constant::ldegree(const ex & s) const
150 return is_equal(ex_to<basic>(s)) ? 1 : 0;
153 ex constant::coeff(const ex & s, int n) const
155 if (is_equal(ex_to<basic>(s)))
156 return n==1 ? _ex1 : _ex0;
158 return n==0 ? *this : _ex0;
161 ex constant::evalf(int level) const
165 } else if (number != 0) {
166 return number->evalf();
173 /** Implementation of ex::diff() for a constant always returns 0.
176 ex constant::derivative(const symbol & s) const
181 int constant::compare_same_type(const basic & other) const
183 GINAC_ASSERT(is_exactly_a<constant>(other));
184 const constant &o = static_cast<const constant &>(other);
186 if (serial == o.serial)
189 return serial < o.serial ? -1 : 1;
192 bool constant::is_equal_same_type(const basic & other) const
194 GINAC_ASSERT(is_exactly_a<constant>(other));
195 const constant &o = static_cast<const constant &>(other);
197 return serial == o.serial;
200 unsigned constant::calchash(void) const
202 hashvalue = golden_ratio_hash(tinfo() ^ serial);
203 // mask out numeric hashes:
204 hashvalue &= 0x7FFFFFFFU;
206 setflag(status_flags::hash_calculated);
212 // new virtual functions which can be overridden by derived classes
218 // non-virtual functions in this class
224 // static member variables
227 unsigned constant::next_serial = 0;
233 /** Pi. (3.14159...) Diverts straight into CLN for evalf(). */
234 const constant Pi("Pi", PiEvalf, "\\pi");
236 /** Euler's constant. (0.57721...) Sometimes called Euler-Mascheroni constant.
237 * Diverts straight into CLN for evalf(). */
238 const constant Euler("Euler", EulerEvalf, "\\gamma_E");
240 /** Catalan's constant. (0.91597...) Diverts straight into CLN for evalf(). */
241 const constant Catalan("Catalan", CatalanEvalf, "G");