* Implementation of relations between expressions */
/*
- * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2002 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 "print.h"
#include "archive.h"
#include "utils.h"
-#include "debugmsg.h"
namespace GiNaC {
GINAC_IMPLEMENT_REGISTERED_CLASS(relational, basic)
//////////
-// default ctor, dtor, copy ctor assignment operator and helpers
+// default ctor, dtor, copy ctor, assignment operator and helpers
//////////
-// public
-
-relational::relational() : basic(TINFO_relational)
-{
- debugmsg("relational default ctor",LOGLEVEL_CONSTRUCT);
-}
-
-// protected
+relational::relational() : basic(TINFO_relational) {}
void relational::copy(const relational & other)
{
o=other.o;
}
-void relational::destroy(bool call_parent)
-{
- if (call_parent) basic::destroy(call_parent);
-}
+DEFAULT_DESTROY(relational)
//////////
// other ctors
// public
-relational::relational(const ex & lhs, const ex & rhs, operators oper) : basic(TINFO_relational)
-{
- debugmsg("relational ctor ex,ex,operator",LOGLEVEL_CONSTRUCT);
- lh=lhs;
- rh=rhs;
- o=oper;
-}
+relational::relational(const ex & lhs, const ex & rhs, operators oper) : basic(TINFO_relational), lh(lhs), rh(rhs), o(oper) {}
//////////
// archiving
//////////
-/** Construct object from archive_node. */
relational::relational(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
{
- debugmsg("relational ctor from archive_node", LOGLEVEL_CONSTRUCT);
unsigned int opi;
if (!(n.find_unsigned("op", opi)))
throw (std::runtime_error("unknown relational operator in archive"));
n.find_ex("rh", rh, sym_lst);
}
-/** Unarchive the object. */
-ex relational::unarchive(const archive_node &n, const lst &sym_lst)
-{
- return (new relational(n, sym_lst))->setflag(status_flags::dynallocated);
-}
-
-/** Archive the object. */
void relational::archive(archive_node &n) const
{
inherited::archive(n);
n.add_unsigned("op", o);
}
+DEFAULT_UNARCHIVE(relational)
+
//////////
-// functions overriding virtual functions from bases classes
+// functions overriding virtual functions from base classes
//////////
// public
-void relational::print(std::ostream & os, unsigned upper_precedence) const
+void relational::print(const print_context & c, unsigned level) const
{
- debugmsg("relational print",LOGLEVEL_PRINT);
- if (precedence<=upper_precedence) os << "(";
- lh.print(os,precedence);
- switch (o) {
- case equal:
- os << "==";
- break;
- case not_equal:
- os << "!=";
- break;
- case less:
- os << "<";
- break;
- case less_or_equal:
- os << "<=";
- break;
- case greater:
- os << ">";
- break;
- case greater_or_equal:
- os << ">=";
- break;
- default:
- os << "(INVALID RELATIONAL OPERATOR)";
+ if (is_a<print_tree>(c)) {
+
+ inherited::print(c, level);
+
+ } else {
+
+ if (is_a<print_python_repr>(c)) {
+ c.s << class_name() << '(';
+ lh.print(c);
+ c.s << ',';
+ rh.print(c);
+ c.s << ",'";
+ } else {
+ if (precedence() <= level)
+ c.s << "(";
+ lh.print(c, precedence());
+ }
+ switch (o) {
+ case equal:
+ c.s << "==";
+ break;
+ case not_equal:
+ c.s << "!=";
+ break;
+ case less:
+ c.s << "<";
+ break;
+ case less_or_equal:
+ c.s << "<=";
+ break;
+ case greater:
+ c.s << ">";
+ break;
+ case greater_or_equal:
+ c.s << ">=";
+ break;
+ default:
+ c.s << "(INVALID RELATIONAL OPERATOR)";
+ }
+ if (is_a<print_python_repr>(c))
+ c.s << "')";
+ else {
+ rh.print(c, precedence());
+ if (precedence() <= level)
+ c.s << ")";
+ }
}
- rh.print(os,precedence);
- if (precedence<=upper_precedence) os << ")";
-}
-
-void relational::printraw(std::ostream & os) const
-{
- debugmsg("relational printraw",LOGLEVEL_PRINT);
- os << "RELATIONAL(";
- lh.printraw(os);
- os << ",";
- rh.printraw(os);
- os << ",";
- switch (o) {
- case equal:
- os << "==";
- break;
- case not_equal:
- os << "!=";
- break;
- case less:
- os << "<";
- break;
- case less_or_equal:
- os << "<=";
- break;
- case greater:
- os << ">";
- break;
- case greater_or_equal:
- os << ">=";
- break;
- default:
- os << "(INVALID RELATIONAL OPERATOR)";
- }
- os << ")";
-}
-
-void relational::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
-{
- debugmsg("relational print csrc", LOGLEVEL_PRINT);
- if (precedence<=upper_precedence)
- os << "(";
-
- // Print left-hand expression
- lh.bp->printcsrc(os, type, precedence);
-
- // Print relational operator
- switch (o) {
- case equal:
- os << "==";
- break;
- case not_equal:
- os << "!=";
- break;
- case less:
- os << "<";
- break;
- case less_or_equal:
- os << "<=";
- break;
- case greater:
- os << ">";
- break;
- case greater_or_equal:
- os << ">=";
- break;
- default:
- os << "(INVALID RELATIONAL OPERATOR)";
- break;
- }
-
- // Print right-hand operator
- rh.bp->printcsrc(os, type, precedence);
-
- if (precedence <= upper_precedence)
- os << ")";
}
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;
+ 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;
}
return i==0 ? lh : rh;
}
-
+
ex relational::eval(int level) const
{
if (level==1)
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
-{
- 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);
-}
-
ex relational::simplify_ncmul(const exvector & v) const
{
return lh.simplify_ncmul(v);
int relational::compare_same_type(const basic & other) const
{
- GINAC_ASSERT(is_exactly_of_type(other, relational));
- const relational & oth=static_cast<const relational &>(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;
+ 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;
}
- if (o<oth.o)
- return -1;
- else
- return 1;
+ 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
return lh.return_type_tinfo();
}
+unsigned relational::calchash(void) 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;
+}
+
//////////
// new virtual functions which can be overridden by derived classes
//////////
// non-virtual functions in this class
//////////
-relational::operator bool() const
+relational::safe_bool relational::make_safe_bool(bool cond) const
+{
+ return cond? &safe_bool_helper::nonnull : 0;
+}
+
+/** 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
{
- // 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))
+ const ex df = lh-rh;
+ if (!is_exactly_a<numeric>(df))
// cannot decide on non-numerical results
- return o==not_equal ? true : false;
-
- int cmpval = ex_to_numeric(df).compare(_num0());
+ return o==not_equal ? make_safe_bool(true) : make_safe_bool(false);
+
switch (o) {
- case equal:
- return cmpval==0;
- case not_equal:
- return cmpval!=0;
- case less:
- return cmpval<0;
- case less_or_equal:
- return cmpval<=0;
- case greater:
- return cmpval>0;
- case greater_or_equal:
- return cmpval>=0;
- default:
- throw(std::logic_error("invalid relational operator"));
+ 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"));
}
}
-//////////
-// static member variables
-//////////
-
-// protected
-
-unsigned relational::precedence = 20;
-
} // namespace GiNaC