1 /** @file fderivative.cpp
3 * Implementation of abstract derivatives of functions. */
6 * GiNaC Copyright (C) 1999-2025 Johannes Gutenberg University Mainz, Germany
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23 #include "fderivative.h"
24 #include "operators.h"
30 GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(fderivative, function,
31 print_func<print_context>(&fderivative::do_print).
32 print_func<print_latex>(&fderivative::do_print_latex).
33 print_func<print_csrc>(&fderivative::do_print_csrc).
34 print_func<print_tree>(&fderivative::do_print_tree))
37 // default constructor
40 fderivative::fderivative()
48 fderivative::fderivative(unsigned ser, unsigned param, const exvector & args) : function(ser, args)
50 parameter_set.insert(param);
53 fderivative::fderivative(unsigned ser, const paramset & params, const exvector & args) : function(ser, args), parameter_set(params)
57 fderivative::fderivative(unsigned ser, const paramset & params, exvector && v) : function(ser, std::move(v)), parameter_set(params)
65 void fderivative::read_archive(const archive_node& n, lst& sym_lst)
67 inherited::read_archive(n, sym_lst);
71 if (n.find_unsigned("param", u, i))
72 parameter_set.insert(u);
78 GINAC_BIND_UNARCHIVER(fderivative);
80 void fderivative::archive(archive_node &n) const
82 inherited::archive(n);
83 auto i = parameter_set.begin(), end = parameter_set.end();
85 n.add_unsigned("param", *i);
92 // functions overriding virtual functions from base classes
95 void fderivative::print(const print_context & c, unsigned level) const
97 // class function overrides print(), but we don't want that
98 basic::print(c, level);
101 void fderivative::do_print(const print_context & c, unsigned level) const
104 auto i = parameter_set.begin(), end = parameter_set.end();
109 c.s << *i << "](" << registered_functions()[serial].name << ")";
110 printseq(c, '(', ',', ')', exprseq::precedence(), function::precedence());
113 void fderivative::do_print_latex(const print_context & c, unsigned level) const
116 c.s << "\\partial_{";
117 auto i = parameter_set.begin(), end = parameter_set.end();
125 c.s << "^{" << order << "}";
126 c.s << "(" << registered_functions()[serial].TeX_name << ")";
127 printseq(c, '(', ',', ')', exprseq::precedence(), function::precedence());
130 void fderivative::do_print_csrc(const print_csrc & c, unsigned level) const
133 auto i = parameter_set.begin(), end = parameter_set.end();
137 c.s << *i << "_" << registered_functions()[serial].name;
138 printseq(c, '(', ',', ')', exprseq::precedence(), function::precedence());
141 void fderivative::do_print_tree(const print_tree & c, unsigned level) const
143 c.s << std::string(level, ' ') << class_name() << " "
144 << registered_functions()[serial].name << " @" << this
145 << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
146 << ", nops=" << nops()
148 auto i = parameter_set.begin(), end = parameter_set.end();
152 c.s << *i << std::endl;
154 i.print(c, level + c.delta_indent);
155 c.s << std::string(level + c.delta_indent, ' ') << "=====" << std::endl;
158 ex fderivative::eval() const
160 // No parameters specified? Then return the function itself
161 if (parameter_set.empty())
162 return function(serial, seq);
164 // If the function in question actually has a derivative, return it
165 if (registered_functions()[serial].has_derivative() && parameter_set.size() == 1)
166 return pderivative(*(parameter_set.begin()));
171 /** The series expansion of derivatives falls back to Taylor expansion.
172 * @see basic::series */
173 ex fderivative::series(const relational & r, int order, unsigned options) const
175 return basic::series(r, order, options);
178 ex fderivative::thiscontainer(const exvector & v) const
180 return fderivative(serial, parameter_set, v);
183 ex fderivative::thiscontainer(exvector && v) const
185 return fderivative(serial, parameter_set, std::move(v));
188 /** Implementation of ex::diff() for derivatives. It applies the chain rule.
190 ex fderivative::derivative(const symbol & s) const
193 for (size_t i=0; i<seq.size(); i++) {
194 ex arg_diff = seq[i].diff(s);
195 if (!arg_diff.is_zero()) {
196 paramset ps = parameter_set;
198 result += arg_diff * fderivative(serial, ps, seq);
204 int fderivative::compare_same_type(const basic & other) const
206 GINAC_ASSERT(is_a<fderivative>(other));
207 const fderivative & o = static_cast<const fderivative &>(other);
209 if (parameter_set != o.parameter_set)
210 return parameter_set < o.parameter_set ? -1 : 1;
212 return inherited::compare_same_type(o);
215 bool fderivative::is_equal_same_type(const basic & other) const
217 GINAC_ASSERT(is_a<fderivative>(other));
218 const fderivative & o = static_cast<const fderivative &>(other);
220 if (parameter_set != o.parameter_set)
223 return inherited::is_equal_same_type(o);
226 bool fderivative::match_same_type(const basic & other) const
228 GINAC_ASSERT(is_a<fderivative>(other));
229 const fderivative & o = static_cast<const fderivative &>(other);
231 return parameter_set == o.parameter_set && inherited::match_same_type(other);
234 /** Expose this object's derivative structure.
236 * Parameter numbers occurring more than once stand for repeated
237 * differentiation with respect to that parameter. If a symbolic function
238 * f(x,y) is differentiated with respect to x, this method will return {0}.
239 * If f(x,y) is differentiated twice with respect to y, it will return {1,1}.
240 * (This corresponds to the way this object is printed.)
242 * @return multiset of function's parameter numbers that are abstractly
244 const paramset& fderivative::derivatives() const
246 return parameter_set;