* 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 "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
//////////
-relational::relational() : basic(TINFO_relational)
-{
- debugmsg("relational default ctor",LOGLEVEL_CONSTRUCT);
-}
+relational::relational() : basic(TINFO_relational) {}
void relational::copy(const relational & other)
{
// 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
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"));
DEFAULT_UNARCHIVE(relational)
//////////
-// functions overriding virtual functions from bases classes
+// functions overriding virtual functions from base classes
//////////
// public
void relational::print(const print_context & c, unsigned level) const
{
- debugmsg("relational print",LOGLEVEL_PRINT);
-
- if (is_of_type(c, print_tree)) {
+ if (is_a<print_tree>(c)) {
inherited::print(c, level);
} else {
- if (precedence() <= level)
- c.s << "(";
- lh.print(c, precedence());
+ 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)";
+ 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(c, precedence());
- if (precedence() <= level)
- 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;
+ 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 (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_31(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_31(v);
+ v ^= lhash;
+
+ // mask out numeric hashes:
+ v &= 0x7FFFFFFFU;
+
+ // 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
//////////
+/** 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 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;
+ const ex df = lh-rh;
if (!is_ex_exactly_of_type(df,numeric))
// cannot decide on non-numerical results
return o==not_equal ? true : false;
- int cmpval = ex_to<numeric>(df).compare(_num0());
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 ex_to<numeric>(df).is_zero();
+ case not_equal:
+ return !ex_to<numeric>(df).is_zero();
+ case less:
+ return ex_to<numeric>(df)<_num0;
+ case less_or_equal:
+ return ex_to<numeric>(df)<=_num0;
+ case greater:
+ return ex_to<numeric>(df)>_num0;
+ case greater_or_equal:
+ return ex_to<numeric>(df)>=_num0;
+ default:
+ throw(std::logic_error("invalid relational operator"));
}
}