'''

Created on Jul 31, 2013

@author: tuna

'''

# lambdas are similar to functions in python with simple syntax

# do define a increment lambda

# first function example below

from functools import reduce

def addNumbers(x, y):

return x + y

print(addNumbers(2, 2))

# output 4

# same thing with short lambda syntax

l = lambda x, y: x + y

print("lambda output ", l(2, 2))

# lambda output 4

# another example return abs value

l = lambda x: abs(x)

print("lambda abs output", l(-1999))

# lambda abs output 1999

print("lambda abs output", l(6))

# lambda abs output 6

# filtering list using lambda

numberList = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]

# filtering numbers greater then 10

print(list(filter(lambda x: x > 0, numberList)))

# output [11, 12, 13, 14, 15]

# showing only even numbers

print(list(filter(lambda x: x % 2 == 0, numberList)))

# output [2, 4, 6, 8, 10, 12, 14]

# lambda different syntax

print((lambda x: abs(x))(-100))

# 100

# lambda different syntax

print((lambda x, y, z: x * y * z)(3, 4, 5))

# output 60

nameList = ["Tornado", "Tuna", "Bob"]

for name in nameList:

print((lambda x: x.startswith('T'))(name))

# True

# True

# False

# lambda filter

# syntax lambda x : True if (condition) else False

test_lambda = lambda x: True if (0 < x < 100) else False

print("test_lambda(90)", test_lambda(90))

test_lambda1 = lambda x: (0 < x < 100)

print("lambda x: (0 < x < 100)", test_lambda1(90))

list_nums = [1, 2, 3, 4, 5, 6, 7, 8, 90, 100, 200, 300, 400, 500]

print(list(filter(test_lambda, list_nums)))

# lambda if else

test_lambda2 = lambda x: x + 1 if x < 100 else (x + 2 if x < 200 else x + 1)

for x in list_nums:

print(test_lambda2(x), end=' ')

# set filter

s = set(filter(lambda x: x > 5, range(100)))

print("'\ns", sorted(s))

s1 = set(map(lambda x: x * 5, range(10)))

print("s1", sorted(s1))

# reduce to single element

r = reduce(lambda x, y: y - x, [1, 2, 3, 4, 5])

# 2-1

# 3-1

# 4-2

# 5-2

print(r)

def f(x): return x % 2 == 0

def square(x): return x * x

print("f(20):", f(20))

print("square:", square(3))

# map

print(list(map(square, range(0, 3))))

# filter

print(list(filter(f, range(0, 10))))