Python（4）操作列表

4.1遍历整个列表

使用for循环

magicians=['a','b','c']for magician in magicians:    print(magician.title()+",that was a great trick!")    print("I can't wait to see you,"+magician.title()+".\n")print("Thank you,everyone!\n")

4.2创建数值列表

range函数

for value in range(1,6):    print(value)numbers=list(range(1,6))        #转为列表print (numbers)even_numbers=list(range(1,10,2))#打印奇数print (even_numbers)print "\n"squares=[]for Value in range(1,11):    square=Value**2             #计算平方    squares.append(square)      #附加到列表squares末尾print(squares)print "\n"

对列表进行简单的统计计算

digits=range(1,20,3)print digitsprint min(digits)print max(digits)print sum(digits)print "\n"

列表解析

squares=[Value**2 for Value in range(1,11)]print(squares)print "\n"

练习

#for Int in range(1,20):    print Intprint "\n"'''#for Int in range(1,1000000):    print Int'''#count=list(range(1,1000000))print min(count)print max(count)print sum(count)print "\n"#INT=list(range(1,20,2))print INTfor Int in range(1,20,2):    print Intprint "\n"#count=[value**3 for value in range (1,10)]print count#counts=[]for value in range(1,10):    count=value**3    counts.append(count)print counts

4.3使用列表一部分

切片

players=['a','b','c','d']print (players[1:3])print (players[:3])print (players[1:])print (players[-3:])#打印最后三个print (players[:])  #打印所有的print ('\n'+"Here are the first three pop star:")for player in players[:3]:    print (player.title())

用切片复制列表

my_food=['aa','bb','cc']friend_food=my_food[:]my_food.append('dd')friend_food.append('ee')print ('\n'+"I like these foods:"+str(my_food))print ('She likes these foods:'+str(friend_food))

练习

#magicians=['a','b','c','d','e']print ('\n'+"Here are the first three pop star:")print (magicians[2:4])#my_pizza=['aa','bb','cc']friend_pizza=my_pizza[:]my_pizza.append('gg')friend_pizza.append('ff')print ('\n'+"I like these pizza:"+str(my_food))print ('She likes these pizza:')for pizza in friend_pizza:    print pizza

4.4元组

创建元组，元组元素不可以被修

dimensions=(200,50)print (dimensions[0])print (dimensions[1])

元组元素，会报错

dimensions[0]=250

遍历元组所有元素

print "\nOriginal dimensions:"for dimension in dimensions:    print(dimension)

通过给存储元组的变量赋值来改变元组变量
print “\nModified dimensions:”

dimensions=(400,250)for dimension in dimensions:    print(dimension)