python官方教程關於list練習

python官方教程，關於list的練習

print 'this is about list test'

a =[1,2,3,4]
a.append(5)
print a

b =[5,6]

a.extend(b)
print a

a.insert(0,0)
print a
a.insert(len(a),10)
print a

a.pop()
print a

a.reverse()
print a

print 'use list as stack'
stack = [1,2]
stack.append(3)
stack.append(4)
print stack

stack.pop()
stack.pop()
print stack

print 'use list as sequence'

from collections import deque
queue = deque(['aa','bb','cc'])
queue.append('dd')
queue.append('ee')
print queue.popleft()
print queue

print 'functional programming tools three important function use'

print 'filter use'
def f(x): return x%3==0 or x%5==0
ll = filter(f,range(2,25))
print ll

print  'map use'
def cube(x): return x*x*x
cc = map(cube,range(1,10))
print cc

print 'reduce use '
def  add(a,b): return a+b
i = reduce(add,range(1,11))
print i

print 'list  comprehension'

squares = [x**2 for x in range(10)]
print squares

mm = [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
print mm


print 'nested list comprehension'

matrix = [
         [1,2,3,4],
         [5,6,7,8],
         [9,10,11,12]
]

print matrix

print 'The following list comprehension will transpose rows and columns:'

new_matrix = [[row[i] for row in matrix] for i in range(4)]

print new_matrix