X-Git-Url: https://git.ucc.asn.au/?p=ipdf%2Fcode.git;a=blobdiff_plain;f=src%2Frational.h;h=e74567db3529cd2e2ee520eac3e5c4eb70558268;hp=b3709ad7f47b067f30986c90ab09f00bb17d8d4f;hb=e297312c8c82e52abd3507c861e85db497ca7e81;hpb=33356addacfe4296ecb613c6c4696f082e351159

diff --git a/src/rational.h b/src/rational.h
index b3709ad..e74567d 100644
--- a/src/rational.h
+++ b/src/rational.h
@@ -8,28 +8,43 @@
 #include "common.h"
 #include <cmath>
 #include <cassert>
+#include "arbint.h"
 
 namespace IPDF
 {
+	
+template <class T> T Tabs(const T & a)
+{
+	return llabs(a);
+}
+
 
-/** Greatest Common Divisor - Euclid's algorithm **/
 
+/* Recursive version  of GCD
 template <class T>
 T gcd(const T & a, const T & b)
 {
-	if (a == 1 || a == 0) return 1;
-	if (b == 0) return a;
-	if (b == a) return a;
+	Debug("Called on %li/%li", int64_t(a), int64_t(b));
+	if (a == T(1) || a == T(0)) return T(1);
+	if (b == T(0)) return a;
+	if (b == a) 
+	{
+		Debug("Equal!");
+		return a;
+	}
+	Debug("Not equal!");
 	
 	if (a > b) return gcd(a-b,b);
 	return gcd(a, b-a);
 }
+*/
 
-/*
+/** Greatest Common Divisor of p and q **/
 template <class T>
 T gcd(const T & p, const T & q)
 {
-	Debug("p/q = %
+
+
 	T g(1);
 	T big(p);
 	T small(q);
@@ -38,24 +53,30 @@ T gcd(const T & p, const T & q)
 		big = q;
 		small = p;
 	}
-	if (small == 0)
+	if (small == T(0))
 		return g;
-	while ((g = big % small) > 0)
+	while ((g = big % small) > T(0))
 	{
+		//Debug("big = %li, small = %li", int64_t(big), int64_t(small));
 		big = small;
 		small = g;
+		//Debug("Loop %u", ++count);
 	}
 	return small;
-}	 
-*/
+}	
+
+
 template <class T = int64_t>
 struct Rational
 {
 	/** Construct from a double.**/
-	Rational(double d = 0) : P(d*1e3), Q(1e3) // Possibly the worst thing ever...
+	Rational(double d=0) : P(d*1e6), Q(1e6) // Possibly the worst thing ever...
 	{
 		Simplify();
-		//CheckAccuracy(d, "Construct from double");
+		//if (!CheckAccuracy(d, "Construct from double"))
+		{
+			//Fatal("Bwah bwah :(");
+		}
 	}
 
 	Rational(const T & _P, const T & _Q) : P(_P), Q(_Q)
@@ -70,13 +91,18 @@ struct Rational
 
 	void Simplify()
 	{
-		if (Q < 0) 
+		if (Q < T(0)) 
 		{
-			P = (P < 0) ? -P : P;
+			P = -P;
 			Q = -Q;
 		}
-
-		T g = gcd(llabs(P),llabs(Q));
+		if (P == T(0))
+		{
+			Q = T(1);
+			return;
+		}
+		T g = gcd(Tabs(P), Tabs(Q));
+		//Debug("Got gcd!");
 		P /= g;
 		Q /= g;
 	}
@@ -94,43 +120,43 @@ struct Rational
 	bool operator>=(const Rational & r) const {return *this == r || *this > r;}
 	bool operator!=(const Rational & r) const {return !(*this == r);}
 
-
-
-	/*
 	Rational operator+(const Rational & r) const 
 	{
-		Rational result = (r.P == 0) ? Rational(P,Q) : Rational(P*r.Q + r.P*Q, Q*r.Q);
-		result.CheckAccuracy(ToDouble() + r.ToDouble(),"+");
+		Rational result = (r.P == T(0)) ? Rational(P,Q) : Rational(P*r.Q + r.P*Q, Q*r.Q);
+		//if (!result.CheckAccuracy(ToDouble() * r.ToDouble(),"+"))
+		//{
+		//	Debug("This is %s (%f) and r is %s (%f)", Str().c_str(), ToDouble(), r.Str().c_str(), r.ToDouble());
+		//}
 		return result;
 	}
 	Rational operator-(const Rational & r) const 
 	{
-		Rational result = (r.P == 0) ? Rational(P,Q) : Rational(P*r.Q - r.P*Q, Q*r.Q);
+		Rational result = (r.P == T(0)) ? Rational(P,Q) : Rational(P*r.Q - r.P*Q, Q*r.Q);
 		result.CheckAccuracy(ToDouble() - r.ToDouble(),"-");
 		return result;
 	}
-	*/
 	Rational operator*(const Rational & r) const 
 	{
 		Rational result(P * r.P, Q * r.Q);
-		if (!result.CheckAccuracy(ToDouble() * r.ToDouble(),"*"))
-		{
-			Debug("This is %s (%f) and r is %s (%f)", Str().c_str(), ToDouble(), r.Str().c_str(), r.ToDouble());
-		}
+		//if (!result.CheckAccuracy(ToDouble() * r.ToDouble(),"*"))
+		//{
+		//	Debug("This is %s (%f) and r is %s (%f)", Str().c_str(), ToDouble(), r.Str().c_str(), r.ToDouble());
+		//}
 		return result;
 	}
 	Rational operator/(const Rational & r) const 
 	{
-		Rational result = (r.P == 0) ? Rational(P,Q) : Rational(P*r.Q + r.P*Q, Q*r.Q);
-		if (!result.CheckAccuracy(ToDouble() / r.ToDouble(),"*"))
-		{
-			Debug("This is %s (%f) and r is %s (%f)", Str().c_str(), ToDouble(), r.Str().c_str(), r.ToDouble());
-		}
+		Rational result(P * r.Q, Q*r.P);
+		//if (!result.CheckAccuracy(ToDouble() / r.ToDouble(),"/"))
+		//{
+		//	Debug("This is %s (%f) and r is %s (%f)", Str().c_str(), ToDouble(), r.Str().c_str(), r.ToDouble());
+		//}
 		return result;
 	}	
 
-	Rational operator+(const Rational & r) const {return Rational(ToDouble()+r.ToDouble());}
-	Rational operator-(const Rational & r) const {return Rational(ToDouble()-r.ToDouble());}
+	/** To cheat, use these **/
+	//Rational operator+(const Rational & r) const {return Rational(ToDouble()+r.ToDouble());}
+	//Rational operator-(const Rational & r) const {return Rational(ToDouble()-r.ToDouble());}
 	//Rational operator*(const Rational & r) const {return Rational(ToDouble()*r.ToDouble());}
 	//Rational operator/(const Rational & r) const {return Rational(ToDouble()/r.ToDouble());}
 
@@ -141,12 +167,14 @@ struct Rational
 	Rational & operator/=(const Rational & r) {this->operator=(*this/r); return *this;}
 
 	double ToDouble() const {return (double)(P) / (double)(Q);}
-	bool CheckAccuracy(double d, const char * msg, double threshold = 1e-6) const
+	bool CheckAccuracy(double d, const char * msg, double threshold = 1e-3) const
 	{
-		double result = fabs(ToDouble() - d) / d;
+		double result = fabs(ToDouble() - d);
+		if (d != 0e0) result /= d;
 		if (result > threshold)
 		{
 			Warn("(%s) : Rational %s (%f) is not close enough at representing %f (%f vs %f)", msg, Str().c_str(), ToDouble(), d, result, threshold);
+			Backtrace();
 			return false;
 		}
 		return true;
@@ -154,7 +182,7 @@ struct Rational
 	std::string Str() const
 	{
 		std::stringstream s;
-		s << (int64_t)P << "/" << (int64_t)Q;
+		s << int64_t(P) << "/" << int64_t(Q);
 		return s.str();
 	}
 	
@@ -171,6 +199,8 @@ inline Rational<int64_t> pow(const Rational<int64_t> & a, const Rational<int64_t
 }
 
 
+
+
 }
 
 #endif //_RATIONAL_H