* Implementation of relations between expressions */
/*
- * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#include <iostream>
#include <stdexcept>
#include "relational.h"
+#include "operators.h"
#include "numeric.h"
-#include "debugmsg.h"
+#include "archive.h"
+#include "utils.h"
-#ifndef NO_GINAC_NAMESPACE
namespace GiNaC {
-#endif // ndef NO_GINAC_NAMESPACE
+
+GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(relational, basic,
+ print_func<print_context>(&relational::do_print).
+ print_func<print_tree>(&basic::do_print_tree).
+ print_func<print_python_repr>(&relational::do_print_python_repr))
//////////
-// default constructor, destructor, copy constructor assignment operator and helpers
+// default constructor
//////////
-// public
+relational::relational() : basic(TINFO_relational) {}
-relational::relational() : basic(TINFO_relational)
-{
- debugmsg("relational default constructor",LOGLEVEL_CONSTRUCT);
-}
+//////////
+// other constructors
+//////////
-relational::~relational()
-{
- debugmsg("relational destructor",LOGLEVEL_DESTRUCT);
- destroy(0);
-}
+// public
-relational::relational(relational const & other)
-{
- debugmsg("relational copy constructor",LOGLEVEL_CONSTRUCT);
- copy(other);
-}
+relational::relational(const ex & lhs, const ex & rhs, operators oper) : basic(TINFO_relational), lh(lhs), rh(rhs), o(oper) {}
-relational const & relational::operator=(relational const & other)
-{
- debugmsg("relational operator=",LOGLEVEL_ASSIGNMENT);
- if (this != &other) {
- destroy(1);
- copy(other);
- }
- return *this;
-}
-
-// protected
+//////////
+// archiving
+//////////
-void relational::copy(relational const & other)
+relational::relational(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst)
{
- basic::copy(other);
- lh=other.lh;
- rh=other.rh;
- o=other.o;
+ unsigned int opi;
+ if (!(n.find_unsigned("op", opi)))
+ throw (std::runtime_error("unknown relational operator in archive"));
+ o = (operators)opi;
+ n.find_ex("lh", lh, sym_lst);
+ n.find_ex("rh", rh, sym_lst);
}
-void relational::destroy(bool call_parent)
+void relational::archive(archive_node &n) const
{
- if (call_parent) basic::destroy(call_parent);
+ inherited::archive(n);
+ n.add_ex("lh", lh);
+ n.add_ex("rh", rh);
+ n.add_unsigned("op", o);
}
+DEFAULT_UNARCHIVE(relational)
+
//////////
-// other constructors
+// functions overriding virtual functions from base classes
//////////
// public
-relational::relational(ex const & lhs, ex const & rhs, operators oper) : basic(TINFO_relational)
+static void print_operator(const print_context & c, relational::operators o)
{
- debugmsg("relational constructor ex,ex,operator",LOGLEVEL_CONSTRUCT);
- lh=lhs;
- rh=rhs;
- o=oper;
+ switch (o) {
+ case relational::equal:
+ c.s << "==";
+ break;
+ case relational::not_equal:
+ c.s << "!=";
+ break;
+ case relational::less:
+ c.s << "<";
+ break;
+ case relational::less_or_equal:
+ c.s << "<=";
+ break;
+ case relational::greater:
+ c.s << ">";
+ break;
+ case relational::greater_or_equal:
+ c.s << ">=";
+ break;
+ default:
+ c.s << "(INVALID RELATIONAL OPERATOR)";
+ break;
+ }
}
-//////////
-// functions overriding virtual functions from bases classes
-//////////
-
-// public
+void relational::do_print(const print_context & c, unsigned level) const
+{
+ if (precedence() <= level)
+ c.s << "(";
+ lh.print(c, precedence());
+ print_operator(c, o);
+ rh.print(c, precedence());
+ if (precedence() <= level)
+ c.s << ")";
+}
-basic * relational::duplicate() const
+void relational::do_print_python_repr(const print_python_repr & c, unsigned level) const
{
- debugmsg("relational duplicate",LOGLEVEL_DUPLICATE);
- return new relational(*this);
+ c.s << class_name() << '(';
+ lh.print(c);
+ c.s << ',';
+ rh.print(c);
+ c.s << ",'";
+ print_operator(c, o);
+ c.s << "')";
}
bool relational::info(unsigned inf) const
{
- switch (inf) {
- case info_flags::relation:
- return 1;
- case info_flags::relation_equal:
- return o==equal;
- case info_flags::relation_not_equal:
- return o==not_equal;
- case info_flags::relation_less:
- return o==less;
- case info_flags::relation_less_or_equal:
- return o==less_or_equal;
- case info_flags::relation_greater:
- return o==greater;
- case info_flags::relation_greater_or_equal:
- return o==greater_or_equal;
- }
- return 0;
+ switch (inf) {
+ case info_flags::relation:
+ return 1;
+ case info_flags::relation_equal:
+ return o==equal;
+ case info_flags::relation_not_equal:
+ return o==not_equal;
+ case info_flags::relation_less:
+ return o==less;
+ case info_flags::relation_less_or_equal:
+ return o==less_or_equal;
+ case info_flags::relation_greater:
+ return o==greater;
+ case info_flags::relation_greater_or_equal:
+ return o==greater_or_equal;
+ }
+ return 0;
}
-int relational::nops() const
+size_t relational::nops() const
{
- return 2;
+ return 2;
}
-ex & relational::let_op(int const i)
+ex relational::op(size_t i) const
{
- GINAC_ASSERT(i>=0);
- GINAC_ASSERT(i<2);
+ GINAC_ASSERT(i<2);
- return i==0 ? lh : rh;
+ return i==0 ? lh : rh;
}
-
+
+ex relational::map(map_function & f) const
+{
+ return (new relational(f(lh), f(rh), o))->setflag(status_flags::dynallocated);
+}
+
ex relational::eval(int level) const
{
- if (level==1) {
- return this->hold();
- }
- if (level == -max_recursion_level) {
- throw(std::runtime_error("max recursion level reached"));
- }
- return (new relational(lh.eval(level-1),rh.eval(level-1),o))->
- setflag(status_flags::dynallocated |
- status_flags::evaluated );
+ if (level==1)
+ return this->hold();
+
+ if (level == -max_recursion_level)
+ throw(std::runtime_error("max recursion level reached"));
+
+ return (new relational(lh.eval(level-1),rh.eval(level-1),o))->setflag(status_flags::dynallocated | status_flags::evaluated);
}
-ex relational::evalf(int level) const
+ex relational::subs(const exmap & m, unsigned options) const
{
- if (level==1) {
- return *this;
- }
- if (level == -max_recursion_level) {
- throw(std::runtime_error("max recursion level reached"));
- }
- return (new relational(lh.eval(level-1),rh.eval(level-1),o))->
- setflag(status_flags::dynallocated);
+ const ex & subsed_lh = lh.subs(m, options);
+ const ex & subsed_rh = rh.subs(m, options);
+
+ if (!are_ex_trivially_equal(lh, subsed_lh) || !are_ex_trivially_equal(rh, subsed_rh))
+ return relational(subsed_lh, subsed_rh, o).subs_one_level(m, options);
+ else
+ return subs_one_level(m, options);
}
-ex relational::simplify_ncmul(exvector const & v) const
+ex relational::eval_ncmul(const exvector & v) const
{
- return lh.simplify_ncmul(v);
+ return lh.eval_ncmul(v);
}
// protected
-int relational::compare_same_type(basic const & other) const
+int relational::compare_same_type(const basic & other) const
{
- GINAC_ASSERT(is_exactly_of_type(other, relational));
- relational const & oth=static_cast<relational const &>(const_cast<basic &>(other));
-
- int cmpval;
-
- if (o == oth.o) {
- cmpval=lh.compare(oth.lh);
- if (cmpval==0) {
- return rh.compare(oth.rh);
- } else {
- return cmpval;
- }
- }
- if (o<oth.o) {
- return -1;
- } else {
- return 1;
- }
+ GINAC_ASSERT(is_exactly_a<relational>(other));
+ const relational &oth = static_cast<const relational &>(other);
+ if (o==oth.o && lh.is_equal(oth.lh) && rh.is_equal(oth.rh))
+ return 0;
+ switch (o) {
+ case equal:
+ case not_equal:
+ if (oth.o!=o)
+ return (o < oth.o) ? -1 : 1;
+ break;
+ case less:
+ if (oth.o!=greater)
+ return (o < oth.o) ? -1 : 1;
+ break;
+ case less_or_equal:
+ if (oth.o!=greater_or_equal)
+ return (o < oth.o) ? -1 : 1;
+ break;
+ case greater:
+ if (oth.o!=less)
+ return (o < oth.o) ? -1 : 1;
+ break;
+ case greater_or_equal:
+ if (oth.o!=less_or_equal)
+ return (o < oth.o) ? -1 : 1;
+ break;
+ }
+ const int lcmpval = lh.compare(oth.rh);
+ return (lcmpval!=0) ? lcmpval : rh.compare(oth.lh);
+}
+
+bool relational::match_same_type(const basic & other) const
+{
+ GINAC_ASSERT(is_exactly_a<relational>(other));
+ const relational &oth = static_cast<const relational &>(other);
+
+ return o == oth.o;
}
-unsigned relational::return_type(void) const
+unsigned relational::return_type() const
{
- GINAC_ASSERT(lh.return_type()==rh.return_type());
- return lh.return_type();
+ GINAC_ASSERT(lh.return_type()==rh.return_type());
+ return lh.return_type();
}
-unsigned relational::return_type_tinfo(void) const
+unsigned relational::return_type_tinfo() const
{
- GINAC_ASSERT(lh.return_type_tinfo()==rh.return_type_tinfo());
- return lh.return_type_tinfo();
+ GINAC_ASSERT(lh.return_type_tinfo()==rh.return_type_tinfo());
+ return lh.return_type_tinfo();
}
-//////////
-// new virtual functions which can be overridden by derived classes
-//////////
-
-// none
+unsigned relational::calchash() const
+{
+ unsigned v = golden_ratio_hash(tinfo());
+ unsigned lhash = lh.gethash();
+ unsigned rhash = rh.gethash();
+
+ v = rotate_left(v);
+ switch(o) {
+ case equal:
+ case not_equal:
+ if (lhash>rhash) {
+ v ^= lhash;
+ lhash = rhash;
+ } else {
+ v ^= rhash;
+ }
+ break;
+ case less:
+ case less_or_equal:
+ v ^= rhash;
+ break;
+ case greater:
+ case greater_or_equal:
+ v ^= lhash;
+ lhash = rhash;
+ break;
+ }
+ v = rotate_left(v);
+ v ^= lhash;
+
+ // store calculated hash value only if object is already evaluated
+ if (flags & status_flags::evaluated) {
+ setflag(status_flags::hash_calculated);
+ hashvalue = v;
+ }
+
+ return v;
+}
//////////
-// non-virtual functions in this class
+// new virtual functions which can be overridden by derived classes
//////////
-#include <iostream>
+/** Left hand side of relational. */
+ex relational::lhs() const
+{
+ return lh;
+}
-relational::operator bool() const
+/** Right hand side of relational. */
+ex relational::rhs() const
{
- // please note that (a<b) == false does not imply (a>=b) == true
- // a false result means the comparison is either false or undecidable
- // (except for !=, where true means unequal or undecidable)
- ex df=lh-rh;
- if (!is_ex_exactly_of_type(df,numeric)) {
- return o==not_equal ? true : false; // cannot decide on non-numerical results
- }
- int cmpval=ex_to_numeric(df).compare(numZERO());
- switch (o) {
- case equal:
- return cmpval==0;
- break;
- case not_equal:
- return cmpval!=0;
- break;
- case less:
- return cmpval<0;
- break;
- case less_or_equal:
- return cmpval<=0;
- break;
- case greater:
- return cmpval>0;
- break;
- case greater_or_equal:
- return cmpval>=0;
- break;
- default:
- throw(std::logic_error("invalid relational operator"));
- }
- return 0;
+ return rh;
}
//////////
-// static member variables
+// non-virtual functions in this class
//////////
-// protected
-
-unsigned relational::precedence=20;
-
-//////////
-// global constants
-//////////
+relational::safe_bool relational::make_safe_bool(bool cond) const
+{
+ return cond? &safe_bool_helper::nonnull : 0;
+}
-const relational some_relational;
-type_info const & typeid_relational=typeid(some_relational);
+/** Cast the relational into a boolean, mainly for evaluation within an
+ * if-statement. Note that (a<b) == false does not imply (a>=b) == true in
+ * the general symbolic case. A false result means the comparison is either
+ * false or undecidable (except of course for !=, where true means either
+ * unequal or undecidable). */
+relational::operator relational::safe_bool() const
+{
+ const ex df = lh-rh;
+ if (!is_exactly_a<numeric>(df))
+ // cannot decide on non-numerical results
+ return o==not_equal ? make_safe_bool(true) : make_safe_bool(false);
+
+ switch (o) {
+ case equal:
+ return make_safe_bool(ex_to<numeric>(df).is_zero());
+ case not_equal:
+ return make_safe_bool(!ex_to<numeric>(df).is_zero());
+ case less:
+ return make_safe_bool(ex_to<numeric>(df)<_num0);
+ case less_or_equal:
+ return make_safe_bool(ex_to<numeric>(df)<=_num0);
+ case greater:
+ return make_safe_bool(ex_to<numeric>(df)>_num0);
+ case greater_or_equal:
+ return make_safe_bool(ex_to<numeric>(df)>=_num0);
+ default:
+ throw(std::logic_error("invalid relational operator"));
+ }
+}
-#ifndef NO_GINAC_NAMESPACE
} // namespace GiNaC
-#endif // ndef NO_GINAC_NAMESPACE
git://www.ginac.de / ginac.git / blobdiff