Horribly unreliable Arbint's and Rational<Arbint>'s

[ipdf/code.git] / src / rational.h

diff --git a/src/rational.h b/src/rational.h
index 41cce09..9dde43a 100644 (file)
--- a/src/rational.h
+++ b/src/rational.h
@@ -16,9 +16,15 @@ namespace IPDF
 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);
@@ -29,6 +35,8 @@ T gcd(const T & a, const T & b)
 template <class T>
 T gcd(const T & p, const T & q)
 {
+
+
        T g(1);
        T big(p);
        T small(q);
@@ -37,15 +45,18 @@ 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
@@ -54,7 +65,10 @@ struct Rational
        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)
@@ -69,17 +83,18 @@ struct Rational
 
        void Simplify()
        {
-               if (Q < 0) 
+               if (Q < T(0)) 
                {
-                       P = (P < 0) ? -P : P;
+                       P = -P;
                        Q = -Q;
                }
-               if (P == 0)
+               if (P == T(0))
                {
-                       Q = 1;
+                       Q = T(1);
                        return;
                }
-               T g = gcd(llabs(P),llabs(Q));
+               T g = gcd(T(llabs(P)),T(llabs(Q)));
+               //Debug("Got gcd!");
                P /= g;
                Q /= g;
        }
@@ -99,13 +114,16 @@ struct Rational
 
        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;
        }
@@ -143,10 +161,12 @@ struct Rational
        double ToDouble() const {return (double)(P) / (double)(Q);}
        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 +174,7 @@ 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 +191,7 @@ inline Rational<int64_t> pow(const Rational<int64_t> & a, const Rational<int64_t
 }
 
 
+
 }
 
 #endif //_RATIONAL_H