LearningPython/Lecture_6 at master · chuanqin3/LearningPython · GitHub

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We started with lambda function:

x = 10
square = x * x
>>> square
100
square = lambda x: x * x
>>> square(4)
16
>>> square(x)
100

Currying: Transforming a multi-argument function into a single-argument, higher-order function.
Know: add(2, 3) = 5
from operator import add
newfunction = lambda f: lambda x: lambda y: f(x, y)
>>> newfunction(add)(2)(3)
5

IMPORTANT: find the square root of a number using Babylonian Method:
def square_root(a):
    x = 1
    while x * x != a:
        print(x)
        x = square_root_update(x, a)
    return x

def square_root_update(x, a):
    return (x + a/x) / 2

CUBE ROOT:
def cube_root(a):
    x = 1
    while x * x * x != a:
        print(x)
        x = cube_root_update(x, a)
    return x

def cube_root_update(x, a):
    return (2 * x + a / (x * x)) / 3