From: Chris Dams <Chris.Dams@mi.infn.it>
Date: Thu, 25 May 2006 16:17:38 +0000 (+0000)
Subject: Possbility for positive symbols/numbers.
X-Git-Tag: release_1-4-0~87
X-Git-Url: https://ginac.de/ginac.git/static/gitweb.css/ginac.git?a=commitdiff_plain;h=f79727f9acf4f78ff71cbe324c333c234c211cb5;p=ginac.git

Possbility for positive symbols/numbers.
---

diff --git a/ginac/constant.cpp b/ginac/constant.cpp
index cff955a9..dd1c170b 100644
--- a/ginac/constant.cpp
+++ b/ginac/constant.cpp
@@ -142,7 +142,9 @@ bool constant::info(unsigned inf) const
 	if (inf == info_flags::polynomial)
 		return true;
 	if (inf == info_flags::real)
-		return domain == domain::real;
+		return domain==domain::real || domain==domain::positive ;
+	if (inf==info_flags::positive || inf==info_flags::nonnegative)
+		return domain == domain::positive;
 	else
 		return inherited::info(inf);
 }
@@ -164,21 +166,21 @@ bool constant::is_polynomial(const ex & var) const
 
 ex constant::conjugate() const
 {
-	if ( domain == domain::real )
+	if ( domain==domain::real || domain==domain::positive )
 		return *this;
 	return conjugate_function(*this).hold();
 }
 
 ex constant::real_part() const
 {
-	if ( domain == domain::real )
+	if ( domain==domain::real || domain==domain::positive )
 		return *this;
 	return real_part_function(*this).hold();
 }
 
 ex constant::imag_part() const
 {
-	if ( domain == domain::real )
+	if ( domain==domain::real || domain==domain::positive )
 		return 0;
 	return imag_part_function(*this).hold();
 }
@@ -244,13 +246,13 @@ unsigned constant::next_serial = 0;
 //////////
 
 /**  Pi. (3.14159...)  Diverts straight into CLN for evalf(). */
-const constant Pi("Pi", PiEvalf, "\\pi", domain::real);
+const constant Pi("Pi", PiEvalf, "\\pi", domain::positive);
 
 /** Euler's constant. (0.57721...)  Sometimes called Euler-Mascheroni constant.
  *  Diverts straight into CLN for evalf(). */
-const constant Euler("Euler", EulerEvalf, "\\gamma_E", domain::real);
+const constant Euler("Euler", EulerEvalf, "\\gamma_E", domain::positive);
 
 /** Catalan's constant. (0.91597...)  Diverts straight into CLN for evalf(). */
-const constant Catalan("Catalan", CatalanEvalf, "G", domain::real);
+const constant Catalan("Catalan", CatalanEvalf, "G", domain::positive);
 
 } // namespace GiNaC
diff --git a/ginac/flags.h b/ginac/flags.h
index 8c4bdfb2..6cf3ea94 100644
--- a/ginac/flags.h
+++ b/ginac/flags.h
@@ -61,7 +61,8 @@ class domain {
 public:
 	enum {
 		complex,
-		real
+		real,
+		positive
 	};
 };
 
@@ -196,7 +197,7 @@ public:
 class info_flags {
 public:
 	enum {
-		// answered by class numeric
+		// answered by class numeric and symbols/constants in particular domains
 		numeric,
 		real,
 		rational,
diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp
index c49fc702..dad9d9e7 100644
--- a/ginac/inifcns.cpp
+++ b/ginac/inifcns.cpp
@@ -190,8 +190,14 @@ static ex abs_eval(const ex & arg)
 {
 	if (is_exactly_a<numeric>(arg))
 		return abs(ex_to<numeric>(arg));
-	else
-		return abs(arg).hold();
+
+	if (arg.info(info_flags::nonnegative))
+		return arg;
+
+	if (is_ex_the_function(arg, abs))
+		return arg;
+
+	return abs(arg).hold();
 }
 
 static void abs_print_latex(const ex & arg, const print_context & c)
diff --git a/ginac/inifcns_trans.cpp b/ginac/inifcns_trans.cpp
index 3f9c380b..657cdfab 100644
--- a/ginac/inifcns_trans.cpp
+++ b/ginac/inifcns_trans.cpp
@@ -246,11 +246,15 @@ static ex log_series(const ex &arg,
 
 static ex log_real_part(const ex & x)
 {
+	if (x.info(info_flags::nonnegative))
+		return log(x).hold();
 	return log(abs(x));
 }
 
 static ex log_imag_part(const ex & x)
 {
+	if (x.info(info_flags::nonnegative))
+		return 0;
 	return atan2(GiNaC::imag_part(x), GiNaC::real_part(x));
 }
 
diff --git a/ginac/symbol.cpp b/ginac/symbol.cpp
index 59dda652..7e3b49d8 100644
--- a/ginac/symbol.cpp
+++ b/ginac/symbol.cpp
@@ -196,7 +196,9 @@ bool symbol::info(unsigned inf) const
 	    inf == info_flags::rational_function)
 		return true;
 	if (inf == info_flags::real)
-		return domain == domain::real;
+		return domain==domain::real || domain==domain::positive;
+	if (inf == info_flags::nonnegative)
+		return domain == domain::positive;
 	else
 		return inherited::info(inf);
 }
@@ -228,14 +230,14 @@ ex symbol::conjugate() const
 
 ex symbol::real_part() const
 {
-	if (domain == domain::real)
+	if (domain==domain::real || domain==domain::positive)
 		return *this;
 	return real_part_function(*this).hold();
 }
 
 ex symbol::imag_part() const
 {
-	if (domain == domain::real)
+	if (domain==domain::real || domain==domain::positive)
 		return 0;
 	return imag_part_function(*this).hold();
 }
diff --git a/ginac/symbol.h b/ginac/symbol.h
index 9c7e526d..90013144 100644
--- a/ginac/symbol.h
+++ b/ginac/symbol.h
@@ -132,7 +132,10 @@ public:
 /** Specialization of is_exactly_a<realsymbol>(obj) for realsymbol objects. */
 template<> inline bool is_exactly_a<realsymbol>(const basic & obj)
 {
-	return (obj.tinfo() == &symbol::tinfo_static) && (static_cast<const symbol &>(obj).get_domain() == domain::real);
+	if (obj.tinfo() != &symbol::tinfo_static)
+		return false;
+	unsigned domain = static_cast<const symbol &>(obj).get_domain();
+	return domain==domain::real || domain==domain::positive;
 }
 
 // wrapper functions around member functions