first commit

frac.py

@@ -0,0 +1,136 @@
+#stores a rational number to perfect precision as a ratio of longs
+#combines with ints to produce a frac ( except __rpow__() ) and with floats to produce a float
+#comparisons with floats might not work perfectly for very similar numbers, I need to test out the float casting a bit
+#it's possible that order w/r/t floats that differ near the limit of precision may not work properly, and even break ordering
+#one solution would be casting floats to fracs instead of vice-versa
+
+import numbers
+
+class frac:
+    
+    def __init__(self, num, den):
+        self.num = long(num)
+        self.den = long(den)
+        self.reduce()
+    
+    def __repr__(self):
+        return 'frac(%d, %d)' % (self.num, self.den)
+    
+    def __str__(self):
+        return '%d/%d' % (self.num, self.den)
+    
+    def __int__(self):
+        return int(self.num / self.den)
+    
+    def __long__(self):
+        return self.num / self.den
+    
+    def __float__(self):
+        return float(self.num) / self.den
+    
+    def __bool__(self):
+        return bool(self.num)
+    
+    def __add__(self, other):
+        if isinstance(other, frac):
+            newnum = self.num * other.den + other.num * self.den
+            newden = self.den * other.den
+            return frac(newnum, newden)
+        elif isinstance(other, (int, long)):
+            return frac(self.num + other * self.den, self.den)
+        elif isinstance(other, float):
+            return other + float(self)
+        else:
+            return NotImplemented
+    
+    def __radd__(self, other):
+        return self + other
+    
+    def __sub__(self, other):
+        if isinstance(other, frac):
+            newnum = self.num * other.den - other.num * self.den
+            newden = self.den * other.den
+            return frac(newnum, newden)
+        elif isinstance(other, (int, long)):
+            return frac(self.num - other * self.den, self.den)
+        elif isinstance(other, float):
+            return float(self) - other
+        else:
+            return NotImplemented
+    
+    def __rsub__(self, other):
+        return -1 * (self - other)
+    
+    def __mul__(self, other):
+        if isinstance(other, frac):
+            return frac(self.num * other.num, self.den * other.den)
+        elif isinstance(other, (int, long)):
+            return frac(self.num * other, self.den)
+        elif isisntance(other, float):
+            return float(self) * other
+        else:
+            return NotImplemented
+    
+    def __rmul__(self, other):
+        return self * other
+    
+    def __truediv__(self, other):
+        if isinstance(other, frac):
+            return frac(self.num * other.num, self.den * other.den)
+        elif isintance(other, (int, long)):
+            return frac(self.num * other, self.den)
+        elif isinstance(other, float):
+            return float(self) * other
+        else:
+            return NotImplemented
+    
+    def __rtruediv__(self, other):
+        if isinstance(other, frac):
+            return frac(other.num * self.den, self.num * other.den)
+        elif isinstance(other, (int, long)):
+            return frac(self.den * other, self.num)
+        elif isinstance(other, float):
+            return other / float(self)
+        else:
+            return NotImplemented
+    
+    def __pow__(self, other):
+        if isinstance(other, frac):
+            return float(self) ** float(other)
+        elif isinstance(other, (int, long)):
+            return frac(self.num ** other, self.den ** other)
+        elif isinstance(other, float):
+            return float(self) ** other
+        else:
+            return NotImplemented
+    
+    def __rpow__(self, other):
+        if isinstance(other, frac):
+            return float(other) ** float(self)
+        elif isinstance(other, (int, long)):
+            return other ** float(self)
+        elif isinstance(other, float):
+            return other ** float(self)
+        else:
+            return NotImplemented
+    
+    def __lt__(self, other):
+        if isinstance(other, frac):
+            return self.num * other.den < other.num * self.den
+        else:
+            return float(self) < other
+    
+    def __le__(self, other):
+        if isinstance(other, frac):
+            return self.num * other.den <= other.num * self.den
+        else:
+            return float(self) <= other
+    
+    def __eq__(self, other):
+        if isinstance(other, frac):
+            return self.num * other.den == other.num * self.den
+        else:
+            return float(self) == other
+    
+    def reduce(self):
+        pass