generous use of auto_ptr to provide better exception safety and make the code
[ginac.git] / ginac / fderivative.cpp
1 /** @file fderivative.cpp
2  *
3  *  Implementation of abstract derivatives of functions. */
4
5 /*
6  *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
7  *
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.
12  *
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.
17  *
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
21  */
22
23 #include <iostream>
24
25 #include "fderivative.h"
26 #include "operators.h"
27 #include "archive.h"
28 #include "utils.h"
29
30 namespace GiNaC {
31
32 GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(fderivative, function,
33   print_func<print_context>(&fderivative::do_print).
34   print_func<print_tree>(&fderivative::do_print_tree))
35
36 //////////
37 // default constructor
38 //////////
39
40 fderivative::fderivative()
41 {
42         tinfo_key = TINFO_fderivative;
43 }
44
45 //////////
46 // other constructors
47 //////////
48
49 fderivative::fderivative(unsigned ser, unsigned param, const exvector & args) : function(ser, args)
50 {
51         parameter_set.insert(param);
52         tinfo_key = TINFO_fderivative;
53 }
54
55 fderivative::fderivative(unsigned ser, const paramset & params, const exvector & args) : function(ser, args), parameter_set(params)
56 {
57         tinfo_key = TINFO_fderivative;
58 }
59
60 fderivative::fderivative(unsigned ser, const paramset & params, std::auto_ptr<exvector> vp) : function(ser, vp), parameter_set(params)
61 {
62         tinfo_key = TINFO_fderivative;
63 }
64
65 //////////
66 // archiving
67 //////////
68
69 fderivative::fderivative(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst)
70 {
71         unsigned i = 0;
72         while (true) {
73                 unsigned u;
74                 if (n.find_unsigned("param", u, i))
75                         parameter_set.insert(u);
76                 else
77                         break;
78                 ++i;
79         }
80 }
81
82 void fderivative::archive(archive_node &n) const
83 {
84         inherited::archive(n);
85         paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
86         while (i != end) {
87                 n.add_unsigned("param", *i);
88                 ++i;
89         }
90 }
91
92 DEFAULT_UNARCHIVE(fderivative)
93
94 //////////
95 // functions overriding virtual functions from base classes
96 //////////
97
98 void fderivative::do_print(const print_context & c, unsigned level) const
99 {
100         c.s << "D[";
101         paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
102         --end;
103         while (i != end)
104                 c.s << *i++ << ",";
105         c.s << *i << "](" << registered_functions()[serial].name << ")";
106         printseq(c, '(', ',', ')', exprseq::precedence(), function::precedence());
107 }
108
109 void fderivative::do_print_tree(const print_tree & c, unsigned level) const
110 {
111         c.s << std::string(level, ' ') << class_name() << " "
112             << registered_functions()[serial].name << " @" << this
113             << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
114             << ", nops=" << nops()
115             << ", params=";
116         paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
117         --end;
118         while (i != end)
119                 c.s << *i++ << ",";
120         c.s << *i << std::endl;
121         for (size_t i=0; i<seq.size(); ++i)
122                 seq[i].print(c, level + c.delta_indent);
123         c.s << std::string(level + c.delta_indent, ' ') << "=====" << std::endl;
124 }
125
126 ex fderivative::eval(int level) const
127 {
128         if (level > 1) {
129                 // first evaluate children, then we will end up here again
130                 return fderivative(serial, parameter_set, evalchildren(level));
131         }
132
133         // No parameters specified? Then return the function itself
134         if (parameter_set.empty())
135                 return function(serial, seq);
136
137         // If the function in question actually has a derivative, return it
138         if (registered_functions()[serial].has_derivative() && parameter_set.size() == 1)
139                 return pderivative(*(parameter_set.begin()));
140
141         return this->hold();
142 }
143
144 /** Numeric evaluation falls back to evaluation of arguments.
145  *  @see basic::evalf */
146 ex fderivative::evalf(int level) const
147 {
148         return basic::evalf(level);
149 }
150
151 /** The series expansion of derivatives falls back to Taylor expansion.
152  *  @see basic::series */
153 ex fderivative::series(const relational & r, int order, unsigned options) const
154 {
155         return basic::series(r, order, options);
156 }
157
158 ex fderivative::thiscontainer(const exvector & v) const
159 {
160         return fderivative(serial, parameter_set, v);
161 }
162
163 ex fderivative::thiscontainer(std::auto_ptr<exvector> vp) const
164 {
165         return fderivative(serial, parameter_set, vp);
166 }
167
168 /** Implementation of ex::diff() for derivatives. It applies the chain rule.
169  *  @see ex::diff */
170 ex fderivative::derivative(const symbol & s) const
171 {
172         ex result;
173         for (size_t i=0; i<seq.size(); i++) {
174                 ex arg_diff = seq[i].diff(s);
175                 if (!arg_diff.is_zero()) {
176                         paramset ps = parameter_set;
177                         ps.insert(i);
178                         result += arg_diff * fderivative(serial, ps, seq);
179                 }
180         }
181         return result;
182 }
183
184 int fderivative::compare_same_type(const basic & other) const
185 {
186         GINAC_ASSERT(is_a<fderivative>(other));
187         const fderivative & o = static_cast<const fderivative &>(other);
188
189         if (parameter_set != o.parameter_set)
190                 return parameter_set < o.parameter_set ? -1 : 1;
191         else
192                 return inherited::compare_same_type(o);
193 }
194
195 bool fderivative::is_equal_same_type(const basic & other) const
196 {
197         GINAC_ASSERT(is_a<fderivative>(other));
198         const fderivative & o = static_cast<const fderivative &>(other);
199
200         if (parameter_set != o.parameter_set)
201                 return false;
202         else
203                 return inherited::is_equal_same_type(o);
204 }
205
206 bool fderivative::match_same_type(const basic & other) const
207 {
208         GINAC_ASSERT(is_a<fderivative>(other));
209         const fderivative & o = static_cast<const fderivative &>(other);
210
211         return parameter_set == o.parameter_set;
212 }
213
214 } // namespace GiNaC