ginac/fderivative.cpp

   1 /** @file fderivative.cpp
   2  *
   3  *  Implementation of abstract derivatives of functions. */
   4
   5 /*
   6  *  GiNaC Copyright (C) 1999-2001 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 "fderivative.h"
  24 #include "print.h"
  25 #include "archive.h"
  26 #include "debugmsg.h"
  27 #include "utils.h"
  28
  29 namespace GiNaC {
  30
  31 GINAC_IMPLEMENT_REGISTERED_CLASS(fderivative, function)
  32
  33 //////////
  34 // default constructor, destructor, copy constructor assignment operator and helpers
  35 //////////
  36
  37 fderivative::fderivative()
  38 {
  39         debugmsg("fderivative default constructor", LOGLEVEL_CONSTRUCT);
  40         tinfo_key = TINFO_fderivative;
  41 }
  42
  43 void fderivative::copy(const fderivative & other)
  44 {
  45         inherited::copy(other);
  46         parameter_set = other.parameter_set;
  47 }
  48
  49 DEFAULT_DESTROY(fderivative)
  50
  51 //////////
  52 // other constructors
  53 //////////
  54
  55 fderivative::fderivative(unsigned ser, unsigned param, const exvector & args) : function(ser, args)
  56 {
  57         debugmsg("fderivative constructor from unsigned,unsigned,exvector", LOGLEVEL_CONSTRUCT);
  58         parameter_set.insert(param);
  59         tinfo_key = TINFO_fderivative;
  60 }
  61
  62 fderivative::fderivative(unsigned ser, const paramset & params, const exvector & args) : function(ser, args), parameter_set(params)
  63 {
  64         debugmsg("fderivative constructor from unsigned,paramset,exvector", LOGLEVEL_CONSTRUCT);
  65         tinfo_key = TINFO_fderivative;
  66 }
  67
  68 fderivative::fderivative(unsigned ser, const paramset & params, exvector * vp) : function(ser, vp), parameter_set(params)
  69 {
  70         debugmsg("fderivative constructor from unsigned,paramset,exvector *", LOGLEVEL_CONSTRUCT);
  71         tinfo_key = TINFO_fderivative;
  72 }
  73
  74 //////////
  75 // archiving
  76 //////////
  77
  78 fderivative::fderivative(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
  79 {
  80         debugmsg("fderivative constructor from archive_node", LOGLEVEL_CONSTRUCT);
  81         unsigned i = 0;
  82         while (true) {
  83                 unsigned u;
  84                 if (n.find_unsigned("param", u, i))
  85                         parameter_set.insert(u);
  86                 else
  87                         break;
  88                 i++;
  89         }
  90 }
  91
  92 void fderivative::archive(archive_node &n) const
  93 {
  94         inherited::archive(n);
  95         paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
  96         while (i != end) {
  97                 n.add_unsigned("param", *i);
  98                 ++i;
  99         }
 100 }
 101
 102 DEFAULT_UNARCHIVE(fderivative)
 103
 104 //////////
 105 // functions overriding virtual functions from base classes
 106 //////////
 107
 108 void fderivative::print(const print_context & c, unsigned level) const
 109 {
 110         debugmsg("fderivative print", LOGLEVEL_PRINT);
 111
 112         if (is_a<print_tree>(c)) {
 113
 114                 c.s << std::string(level, ' ') << class_name() << " "
 115                     << registered_functions()[serial].name
 116                     << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
 117                     << ", nops=" << nops()
 118                     << ", params=";
 119                 paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
 120                 --end;
 121                 while (i != end)
 122                         c.s << *i++ << ",";
 123                 c.s << *i << std::endl;
 124                 unsigned delta_indent = static_cast<const print_tree &>(c).delta_indent;
 125                 for (unsigned i=0; i<seq.size(); ++i)
 126                         seq[i].print(c, level + delta_indent);
 127                 c.s << std::string(level + delta_indent, ' ') << "=====" << std::endl;
 128
 129         } else {
 130
 131                 c.s << "D[";
 132                 paramset::const_iterator i = parameter_set.begin(), end = parameter_set.end();
 133                 --end;
 134                 while (i != end)
 135                         c.s << *i++ << ",";
 136                 c.s << *i << "](" << registered_functions()[serial].name << ")";
 137                 printseq(c, '(', ',', ')', exprseq::precedence(), function::precedence());
 138         }
 139 }
 140
 141 ex fderivative::eval(int level) const
 142 {
 143         if (level > 1) {
 144                 // first evaluate children, then we will end up here again
 145                 return fderivative(serial, parameter_set, evalchildren(level));
 146         }
 147
 148         // No parameters specified? Then return the function itself
 149         if (parameter_set.empty())
 150                 return function(serial, seq);
 151
 152         // If the function in question actually has a derivative, return it
 153         if (registered_functions()[serial].has_derivative() && parameter_set.size() == 1)
 154                 return pderivative(*(parameter_set.begin()));
 155
 156         return this->hold();
 157 }
 158
 159 /** Numeric evaluation falls back to evaluation of arguments.
 160  *  @see basic::evalf */
 161 ex fderivative::evalf(int level) const
 162 {
 163         return basic::evalf(level);
 164 }
 165
 166 /** The series expansion of derivatives falls back to Taylor expansion.
 167  *  @see basic::series */
 168 ex fderivative::series(const relational & r, int order, unsigned options) const
 169 {
 170         return basic::series(r, order, options);
 171 }
 172
 173 ex fderivative::thisexprseq(const exvector & v) const
 174 {
 175         return fderivative(serial, parameter_set, v);
 176 }
 177
 178 ex fderivative::thisexprseq(exvector * vp) const
 179 {
 180         return fderivative(serial, parameter_set, vp);
 181 }
 182
 183 /** Implementation of ex::diff() for derivatives. It applies the chain rule.
 184  *  @see ex::diff */
 185 ex fderivative::derivative(const symbol & s) const
 186 {
 187         ex result;
 188         for (unsigned i=0; i!=seq.size(); i++) {
 189                 ex arg_diff = seq[i].diff(s);
 190                 if (!arg_diff.is_zero()) {
 191                         paramset ps = parameter_set;
 192                         ps.insert(i);
 193                         result += arg_diff * fderivative(serial, ps, seq);
 194                 }
 195         }
 196         return result;
 197 }
 198
 199 int fderivative::compare_same_type(const basic & other) const
 200 {
 201         GINAC_ASSERT(is_of_type(other, fderivative));
 202         const fderivative & o = static_cast<const fderivative &>(other);
 203
 204         if (parameter_set != o.parameter_set)
 205                 return parameter_set < o.parameter_set ? -1 : 1;
 206         else
 207                 return inherited::compare_same_type(o);
 208 }
 209
 210 bool fderivative::is_equal_same_type(const basic & other) const
 211 {
 212         GINAC_ASSERT(is_of_type(other, fderivative));
 213         const fderivative & o = static_cast<const fderivative &>(other);
 214
 215         if (parameter_set != o.parameter_set)
 216                 return false;
 217         else
 218                 return inherited::is_equal_same_type(o);
 219 }
 220
 221 bool fderivative::match_same_type(const basic & other) const
 222 {
 223         GINAC_ASSERT(is_of_type(other, fderivative));
 224         const fderivative & o = static_cast<const fderivative &>(other);
 225
 226         return parameter_set == o.parameter_set;
 227 }
 228
 229 } // namespace GiNaC