init repo

chapter-03/interval/interval.py

@@ -0,0 +1,25 @@
+class REAL:  # nested.py
+    def __init__(self, l, u):
+        self.lower = l
+        self.upper = u
+
+    def asString(self, n):
+        l = self.lower(n)
+        u = self.upper(n)
+        return ("[ " + l.numerator.digits() + "/" + l.denominator.digits() +
+                ", " + u.numerator.digits() + "/" + u.denominator.digits() + "]")
+
+    def __add__(self, y):
+        return REAL_add(self, y)
+
+
+class REAL_add(REAL):
+    def __init__(self, x, y):
+        self.x = x
+        self.y = y
+
+    def lower(self, n):
+        return self.x.lower(n) + self.y.lower(n)
+
+    def upper(self, n):
+        return self.x.upper(n) + self.y.upper(n)

chapter-03/interval/main.py

@@ -0,0 +1,17 @@
+from interval import REAL
+from gmpy2 import mpq # rationale Zahlen
+
+
+def lower_one(n):
+    return mpq(1,1)-mpq(1,n)
+def upper_one(n):
+    return mpq(1,1)+mpq(1,n)
+
+x = REAL(lower_one,upper_one); y = x + x
+
+print ("x: "+x.asString(10))
+print ("y: "+y.asString(10))
+
+
+print ("x: "+x.asString(10000))
+print ("y: "+y.asString(10000))