X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fsymbol.cpp;h=169ee631bc5ef0361f855ef3e7267a764e58c345;hp=b32418f1aa50e70ff1029dc52308568f30a3b2e4;hb=4e3a4ac2bcb0837611ea31bc8fc05d84a20c33ac;hpb=4e3986a8583584945681ee2dc1560e0fc08e4978

diff --git a/ginac/symbol.cpp b/ginac/symbol.cpp
index b32418f1..169ee631 100644
--- a/ginac/symbol.cpp
+++ b/ginac/symbol.cpp
@@ -1,8 +1,9 @@
 /** @file symbol.cpp
  *
- *  Implementation of GiNaC's symbolic objects.
- *
- *  GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
+ *  Implementation of GiNaC's symbolic objects. */
+
+/*
+ *  GiNaC Copyright (C) 1999-2001 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
@@ -24,72 +25,99 @@
 
 #include "symbol.h"
 #include "lst.h"
-#include "utils.h"
 #include "idx.h"
+#include "archive.h"
+#include "debugmsg.h"
+#include "utils.h"
+
+namespace GiNaC {
+
+GINAC_IMPLEMENT_REGISTERED_CLASS_NO_CTORS(symbol, basic)
 
 //////////
-// default constructor, destructor, copy constructor assignment operator and helpers
+// default ctor, dtor, copy ctor assignment operator and helpers
 //////////
 
-symbol::symbol() : basic(TINFO_symbol)
+symbol::symbol() : inherited(TINFO_symbol), serial(next_serial++)
 {
-    debugmsg("symbol default constructor",LOGLEVEL_CONSTRUCT);
-    serial=next_serial++;
-    name=autoname_prefix()+ToString(serial);
-    asexinfop=new assigned_ex_info;
-    setflag(status_flags::evaluated);
+	debugmsg("symbol default ctor", LOGLEVEL_CONSTRUCT);
+	name = autoname_prefix()+ToString(serial);
+	asexinfop = new assigned_ex_info;
+	setflag(status_flags::evaluated | status_flags::expanded);
 }
 
-symbol::~symbol()
+/** For use by copy ctor and assignment operator. */
+void symbol::copy(const symbol & other)
 {
-    debugmsg("symbol destructor",LOGLEVEL_DESTRUCT);
-    destroy(0);
+	inherited::copy(other);
+	name = other.name;
+	serial = other.serial;
+	asexinfop = other.asexinfop;
+	++asexinfop->refcount;
 }
 
-symbol::symbol(symbol const & other)
+void symbol::destroy(bool call_parent)
 {
-    debugmsg("symbol copy constructor",LOGLEVEL_CONSTRUCT);
-    copy(other);
+	if (--asexinfop->refcount == 0)
+		delete asexinfop;
+	if (call_parent)
+		inherited::destroy(call_parent);
 }
 
-void symbol::copy(symbol const & other)
+//////////
+// other ctors
+//////////
+
+// public
+
+symbol::symbol(const symbol & other)
 {
-    basic::copy(other);
-    name=other.name;
-    serial=other.serial;
-    asexinfop=other.asexinfop;
-    ++asexinfop->refcount;
+	debugmsg("symbol copy ctor", LOGLEVEL_CONSTRUCT);
+	copy(other);
 }
 
-void symbol::destroy(bool call_parent)
+symbol::symbol(const std::string & initname) : inherited(TINFO_symbol)
 {
-    if (--asexinfop->refcount == 0) {
-        delete asexinfop;
-    }
-    if (call_parent) {
-        basic::destroy(call_parent);
-    }
+	debugmsg("symbol ctor from string", LOGLEVEL_CONSTRUCT);
+	name = initname;
+	serial = next_serial++;
+	asexinfop = new assigned_ex_info;
+	setflag(status_flags::evaluated | status_flags::expanded);
 }
 
-// how should the following be interpreted?
-// symbol x;
-// symbol y;
-// x=y;
-// probably as: x=ex(y);
-
 //////////
-// other constructors
+// archiving
 //////////
 
-// public
+/** Construct object from archive_node. */
+symbol::symbol(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
+{
+	debugmsg("symbol ctor from archive_node", LOGLEVEL_CONSTRUCT);
+	serial = next_serial++;
+	if (!(n.find_string("name", name)))
+		name = autoname_prefix() + ToString(serial);
+	asexinfop = new assigned_ex_info;
+	setflag(status_flags::evaluated);
+}
 
-symbol::symbol(string const & initname) : basic(TINFO_symbol)
+/** Unarchive the object. */
+ex symbol::unarchive(const archive_node &n, const lst &sym_lst)
 {
-    debugmsg("symbol constructor from string",LOGLEVEL_CONSTRUCT);
-    name=initname;
-    serial=next_serial++;
-    asexinfop=new assigned_ex_info;
-    setflag(status_flags::evaluated);
+	ex s = (new symbol(n, sym_lst))->setflag(status_flags::dynallocated);
+	
+	// If symbol is in sym_lst, return the existing symbol
+	for (unsigned i=0; i<sym_lst.nops(); i++) {
+		if (is_ex_of_type(sym_lst.op(i), symbol) && (ex_to_symbol(sym_lst.op(i)).name == ex_to_symbol(s).name))
+			return sym_lst.op(i);
+	}
+	return s;
+}
+
+/** Archive the object. */
+void symbol::archive(archive_node &n) const
+{
+	inherited::archive(n);
+	n.add_string("name", name);
 }
 
 //////////
@@ -98,121 +126,167 @@ symbol::symbol(string const & initname) : basic(TINFO_symbol)
 
 // public
 
-basic * symbol::duplicate() const
+basic *symbol::duplicate() const
+{
+	debugmsg("symbol duplicate", LOGLEVEL_DUPLICATE);
+	return new symbol(*this);
+}
+
+void symbol::print(std::ostream & os, unsigned upper_precedence) const
+{
+	debugmsg("symbol print",LOGLEVEL_PRINT);
+	os << name;
+}
+
+void symbol::printraw(std::ostream & os) const
+{
+	debugmsg("symbol printraw",LOGLEVEL_PRINT);
+	os << "symbol(" << "name=" << name << ",serial=" << serial
+	   << ",hash=" << hashvalue << ",flags=" << flags << ")";
+}
+
+void symbol::printtree(std::ostream & os, unsigned indent) const
+{
+	debugmsg("symbol printtree",LOGLEVEL_PRINT);
+	os << std::string(indent,' ') << name << " (symbol): "
+	   << "serial=" << serial
+	   << ", hash=" << hashvalue
+	   << " (0x" << std::hex << hashvalue << std::dec << ")"
+	   << ", flags=" << flags << std::endl;
+}
+
+void symbol::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
 {
-    debugmsg("symbol duplicate",LOGLEVEL_DUPLICATE);
-    return new symbol(*this);
+	debugmsg("symbol print csrc", LOGLEVEL_PRINT);
+	os << name;
 }
 
 bool symbol::info(unsigned inf) const
 {
-    if (inf==info_flags::symbol) return true;
-    if (inf==info_flags::polynomial || inf==info_flags::integer_polynomial || inf==info_flags::rational_polynomial || inf==info_flags::rational_function) {
-        return true;
-    } else {
-        return basic::info(inf);
-    }
+	if (inf==info_flags::symbol) return true;
+	if (inf==info_flags::polynomial ||
+	    inf==info_flags::integer_polynomial ||
+	    inf==info_flags::cinteger_polynomial ||
+	    inf==info_flags::rational_polynomial ||
+	    inf==info_flags::crational_polynomial ||
+	    inf==info_flags::rational_function)
+		return true;
+	else
+		return inherited::info(inf);
 }
 
 ex symbol::expand(unsigned options) const
 {
-    return this->hold();
+	return this->hold();
 }
 
-bool symbol::has(ex const & other) const
+bool symbol::has(const ex & other) const
 {
-    if (is_equal(*other.bp)) return true;
-    return false;
+	if (this->is_equal(*other.bp))
+		return true;
+	else
+		return false;
 }
 
-int symbol::degree(symbol const & s) const
+int symbol::degree(const symbol & s) const
 {
-    return compare_same_type(s)==0 ? 1 : 0;
+	return compare_same_type(s)==0 ? 1 : 0;
 }
 
-int symbol::ldegree(symbol const & s) const
+int symbol::ldegree(const symbol & s) const
 {
-    return compare_same_type(s)==0 ? 1 : 0;
+	return compare_same_type(s)==0 ? 1 : 0;
 }
 
-ex symbol::coeff(symbol const & s, int const n) const
+ex symbol::coeff(const symbol & s, int n) const
 {
-    if (compare_same_type(s)==0) {
-        return n==1 ? exONE() : exZERO();
-    } else {
-        return n==0 ? *this : exZERO();
-    }
+	if (compare_same_type(s)==0)
+		return n==1 ? _ex1() : _ex0();
+	else
+		return n==0 ? *this : _ex0();
 }
 
 ex symbol::eval(int level) const
 {
-    if (level == -max_recursion_level) {
-        throw(std::runtime_error("max recursion level reached"));
-    }
-    
-    if (asexinfop->is_assigned) {
-        setflag(status_flags::evaluated);
-        if (level==1) {
-            return (asexinfop->assigned_expression);
-        } else {
-            return (asexinfop->assigned_expression).eval(level);
-        }
-    } else {
-        return this->hold();
-    }
+	if (level == -max_recursion_level)
+		throw(std::runtime_error("max recursion level reached"));
+	
+	if (asexinfop->is_assigned) {
+		setflag(status_flags::evaluated);
+		if (level==1)
+			return (asexinfop->assigned_expression);
+		else
+			return (asexinfop->assigned_expression).eval(level);
+	} else {
+		return this->hold();
+	}
 }
 
-ex symbol::subs(lst const & ls, lst const & lr) const
+ex symbol::subs(const lst & ls, const lst & lr) const
 {
-    ASSERT(ls.nops()==lr.nops());
-#ifdef DOASSERT
-    for (int i=0; i<ls.nops(); i++) {
-        ASSERT(is_ex_exactly_of_type(ls.op(i),symbol)||
-               is_ex_of_type(ls.op(i),idx));
-    }
-#endif // def DOASSERT
-
-    for (int i=0; i<ls.nops(); i++) {
-        if (is_ex_exactly_of_type(ls.op(i),symbol)) {
-            if (compare_same_type(ex_to_symbol(ls.op(i)))==0) return lr.op(i);
-        }
-    }
-    return *this;
+	GINAC_ASSERT(ls.nops()==lr.nops());
+#ifdef DO_GINAC_ASSERT
+	for (unsigned i=0; i<ls.nops(); i++)
+		GINAC_ASSERT(is_ex_exactly_of_type(ls.op(i),symbol)||
+		             is_ex_of_type(ls.op(i),idx));
+#endif // def DO_GINAC_ASSERT
+
+	for (unsigned i=0; i<ls.nops(); i++) {
+		if (is_ex_exactly_of_type(ls.op(i),symbol)) {
+			if (compare_same_type(ex_to_symbol(ls.op(i)))==0)
+				return lr.op(i);
+		}
+	}
+	return *this;
 }
 
 // protected
 
-int symbol::compare_same_type(basic const & other) const
+/** Implementation of ex::diff() for single differentiation of a symbol.
+ *  It returns 1 or 0.
+ *
+ *  @see ex::diff */
+ex symbol::derivative(const symbol & s) const
 {
-    ASSERT(is_of_type(other,symbol));
-    const symbol *o = static_cast<const symbol *>(&other);
-    if (serial==o->serial) return 0;
-    return serial < o->serial ? -1 : 1;
+	if (compare_same_type(s))
+		return _ex0();
+	else
+		return _ex1();
 }
 
-bool symbol::is_equal_same_type(basic const & other) const
+int symbol::compare_same_type(const basic & other) const
 {
-    ASSERT(is_of_type(other,symbol));
-    const symbol *o = static_cast<const symbol *>(&other);
-    return serial==o->serial;
+	GINAC_ASSERT(is_of_type(other,symbol));
+	const symbol *o = static_cast<const symbol *>(&other);
+	if (serial==o->serial) return 0;
+	return serial < o->serial ? -1 : 1;
+}
+
+bool symbol::is_equal_same_type(const basic & other) const
+{
+	GINAC_ASSERT(is_of_type(other,symbol));
+	const symbol *o = static_cast<const symbol *>(&other);
+	return serial==o->serial;
 }
 
 unsigned symbol::return_type(void) const
 {
-    return return_types::commutative;
+	return return_types::commutative;
 }
    
 unsigned symbol::return_type_tinfo(void) const
 {
-    return tinfo_key;
+	return tinfo_key;
 }
 
 unsigned symbol::calchash(void) const
 {
-    // return golden_ratio_hash(tinfo()) ^ serial;
-    hashvalue=golden_ratio_hash(golden_ratio_hash(0x55555555U ^ serial));
-    setflag(status_flags::hash_calculated);
-    return hashvalue;
+	// this is where the schoolbook method
+	// (golden_ratio_hash(tinfo()) ^ serial)
+	// is not good enough yet...
+	hashvalue = golden_ratio_hash(golden_ratio_hash(tinfo()) ^ serial);
+	setflag(status_flags::hash_calculated);
+	return hashvalue;
 }
 
 //////////
@@ -227,28 +301,30 @@ unsigned symbol::calchash(void) const
 
 // public
 
-void symbol::assign(ex const & value)
+void symbol::assign(const ex & value)
 {
-    asexinfop->is_assigned=1;
-    asexinfop->assigned_expression=value;
-    clearflag(status_flags::evaluated);
+	asexinfop->is_assigned = 1;
+	asexinfop->assigned_expression = value;
+	clearflag(status_flags::evaluated | status_flags::expanded);
 }
 
 void symbol::unassign(void)
 {
-    if (asexinfop->is_assigned) {
-        asexinfop->is_assigned=0;
-        asexinfop->assigned_expression=exZERO();
-    }
-    setflag(status_flags::evaluated);
+	if (asexinfop->is_assigned) {
+		asexinfop->is_assigned = 0;
+		asexinfop->assigned_expression = _ex0();
+	}
+	setflag(status_flags::evaluated | status_flags::expanded);
 }
 
 // private
 
-string & symbol::autoname_prefix(void)
+/** Symbols not constructed with a string get one assigned using this
+ *  prefix and a number. */
+std::string & symbol::autoname_prefix(void)
 {
-    static string * s=new string("symbol");
-    return *s;
+	static std::string *s = new std::string("symbol");
+	return *s;
 }
 
 //////////
@@ -257,16 +333,7 @@ string & symbol::autoname_prefix(void)
 
 // private
 
-unsigned symbol::next_serial=0;
-
-// string const symbol::autoname_prefix="symbol";
-
-//////////
-// global constants
-//////////
-
-const symbol some_symbol;
-type_info const & typeid_symbol=typeid(some_symbol);
+unsigned symbol::next_serial = 0;
 
 //////////
 // subclass assigned_ex_info
@@ -276,3 +343,5 @@ type_info const & typeid_symbol=typeid(some_symbol);
 symbol::assigned_ex_info::assigned_ex_info(void) : is_assigned(0), refcount(1)
 {
 }
+
+} // namespace GiNaC