/*
- rational.hh -- declare
+ rational.hh -- declare rational helpers
source file of the Flower Library
- (c) 1997 Han-Wen Nienhuys <hanwen@stack.nl>
+ (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
*/
#ifndef RATIONAL_HH
#define RATIONAL_HH
-#include <Rational.h>
-/// print a Rational. To be called from the debugger
-void print_rat(Rational const&);
+#include "compare.hh"
+#include "arithmetic-operator.hh"
+#include "flower-proto.hh"
+#include "string.hh"
+
+
+/**
+ Rational numbers. Included is support for + and - infinity.
+ */
+class Rational {
+ /**
+ Sign of rational.
+ -2, .. 2
+
+ -2,2 is - and + infinity.
+ -1,1 is negative and positive.
+ 0 if *this is zero.
+ */
+ int sign_;
+ unsigned int num_, den_;
+ void normalise ();
+ void copy (Rational const &);
+
+public:
+ void set_infinite (int sign);
+ bool is_infinity () const;
+ void invert ();
+ int num () const { return sign_ * num_; }
+ int den () const { return den_; }
+
+ Rational trunc_rat () const;
+ Rational div_rat (Rational) const;
+ Rational mod_rat (Rational) const;
+ void negate ();
+ // operator bool () const;
+ int to_int () const;
+ operator double () const;
+ Rational operator - () const;
+ /**
+ Initialize to 0.
+ */
+ Rational ();
+ Rational (int);
+ Rational (int, int);
+ Rational (double);
+ Rational (Rational const&r) { copy (r);}
+ Rational &operator = (Rational const &r) {
+ copy (r); return *this;
+ }
+
+ Rational &operator *= (Rational);
+ Rational &operator /= (Rational);
+ Rational &operator += (Rational);
+ Rational &operator -= (Rational);
+ Rational &operator %= (Rational);
+ static int compare (Rational const&, Rational const&);
+ int sign () const;
+ String to_string () const;
+};
+
+IMPLEMENT_ARITHMETIC_OPERATOR (Rational, / );
+IMPLEMENT_ARITHMETIC_OPERATOR (Rational, + );
+IMPLEMENT_ARITHMETIC_OPERATOR (Rational, * );
+IMPLEMENT_ARITHMETIC_OPERATOR (Rational, - );
+IMPLEMENT_ARITHMETIC_OPERATOR (Rational, % );
+
+INSTANTIATE_COMPARE (Rational const&, Rational::compare);
+
+int compare (Rational const&,Rational const&);
+int sign (Rational r);
+
+inline void
+Rational::copy (Rational const&r)
+{
+ sign_ = r.sign_;
+ num_ = r.num_;
+ den_ = r.den_;
+}
+
+#if 0
+ostream &
+operator << (ostream &, Rational);
+#endif
+
+const Rational infinity_rat = INT_MAX;
#endif // RATIONAL_HH