Just another update

Task/Fibonacci-sequence/Python/fibonacci-sequence-10.py

@@ -0,0 +1,10 @@
+def fib():
+    """Yield fib[n+1] + fib[n]"""
+    yield 1  # have to start somewhere
+    lhs, rhs = fib(), fib()
+    yield next(lhs) # move lhs one iteration ahead
+    while True:
+        yield next(lhs)+next(rhs)
+
+f=fib()
+print [next(f) for _ in range(9)]

Task/Fibonacci-sequence/Python/fibonacci-sequence-5.py

@@ -1,5 +1,5 @@
-def fibGen():
-    f0, f1 = 0, 1
-    while True:
-        yield f0
-        f0, f1 = f1, f0+f1
+def fibFastRec(n):
+    def fib(prvprv, prv, c):
+        if c < 1: return prvprv
+        else: return fib(prv, prvprv + prv, c - 1)
+    return fib(0, 1, n)

Task/Fibonacci-sequence/Python/fibonacci-sequence-6.py

@@ -1,14 +1,4 @@
->>> fg = fibGen()
->>> for x in range(9):
-    print fg.next()
-
-0
-1
-1
-2
-3
-5
-8
-13
-21
->>>
+def fibGen(n,a=0,b=1):
+    while n>0:
+        yield a
+        a,b,n = b,a+b,n-1

Task/Fibonacci-sequence/Python/fibonacci-sequence-7.py

@@ -1,30 +1,3 @@
-def prevPowTwo(n):
-    'Gets the power of two that is less than or equal to the given input'
-    if ((n & -n) == n):
-        return n
-    else:
-        n -= 1
-        n |= n >> 1
-        n |= n >> 2
-        n |= n >> 4
-        n |= n >> 8
-        n |= n >> 16
-        n += 1
-        return (n/2)
+>>> [i for i in fibGen(11)]
 
-def crazyFib(n):
-    'Crazy fast fibonacci number calculation'
-    powTwo = prevPowTwo(n)
-
-    q = r = i = 1
-    s = 0
-
-    while(i < powTwo):
-        i *= 2
-        q, r, s = q*q + r*r, r * (q + s), (r*r + s*s)
-
-    while(i < n):
-        i += 1
-        q, r, s = q+r, q, r
-
-    return q
+[0,1,1,2,3,5,8,13,21,34,55]

Task/Fibonacci-sequence/Python/fibonacci-sequence-8.py

@@ -1,7 +1,30 @@
-def fib(n, c={0:1, 1:1}):
-    if n not in c:
-        x = n // 2
-        c[n] = fib(x-1) * fib(n-x-1) + fib(x) * fib(n - x)
-    return c[n]
+def prevPowTwo(n):
+    'Gets the power of two that is less than or equal to the given input'
+    if ((n & -n) == n):
+        return n
+    else:
+        n -= 1
+        n |= n >> 1
+        n |= n >> 2
+        n |= n >> 4
+        n |= n >> 8
+        n |= n >> 16
+        n += 1
+        return (n/2)
 
-fib(10000000)  # calculating it takes a few seconds, printing it takes eons
+def crazyFib(n):
+    'Crazy fast fibonacci number calculation'
+    powTwo = prevPowTwo(n)
+
+    q = r = i = 1
+    s = 0
+
+    while(i < powTwo):
+        i *= 2
+        q, r, s = q*q + r*r, r * (q + s), (r*r + s*s)
+
+    while(i < n):
+        i += 1
+        q, r, s = q+r, q, r
+
+    return q

Task/Fibonacci-sequence/Python/fibonacci-sequence-9.py

@@ -0,0 +1,7 @@
+def fib(n, c={0:1, 1:1}):
+    if n not in c:
+        x = n // 2
+        c[n] = fib(x-1) * fib(n-x-1) + fib(x) * fib(n - x)
+    return c[n]
+
+fib(10000000)  # calculating it takes a few seconds, printing it takes eons