Python学习笔记——基本数据结构

列表list

List是python的一个内置动态数组对象，它的基本使用方式如下：

    shoplist = ['apple', 'mango', 'carrot', 'banana']

    print 'I have', len(shoplist),'items to purchase.'

    print 'These items are:', # Notice the comma at end of the line
    for item in shoplist:
        print item,


    print ' I also have to buy rice.'
    shoplist.append('rice')
    print 'My shopping list is now', shoplist

    print 'I will sort my list now'
    shoplist.sort()
    print 'Sorted shopping list is', shoplist

    print 'The first item I will buy is', shoplist[0]
    olditem = shoplist[0]
    del shoplist[0]

    print 'I bought the', olditem
    print 'My shopping list is now', shoplist

 

元组Tuple

Python的typle通过小括号初始化，是一个只读对象。不过它的成员具有数组的访问方式。

    zoo = ('wolf', 'elephant', 'penguin')
    print 'Number of animals in the zoo is', len(zoo)

    new_zoo = ('monkey', 'dolphin', zoo)
    print 'Number of animals in the new zoo is', len(new_zoo)
    print 'All animals in new zoo are', new_zoo
    print 'Animals brought from old zoo are', new_zoo[2]
    print 'Last animal brought from old zoo is', new_zoo[2][2]

 

字典dict

Dict是一个查询式的数据结构，它的基本用法如下：

ab = {    'Swaroop' : 'swaroopch@byteofpython.info',
        'Larry' : 'larry@wall.org',
        'Matsumoto' : 'matz@ruby-lang.org',
        'Spammer' : 'spammer@hotmail.com'
        }

print "Swaroop's address is %s" % ab['Swaroop']

# Adding a key/value pair
ab['Guido'] = 'guido@python.org'

# Deleting a key/value pair
del ab['Spammer']

print ' There are %d contacts in the address-book ' % len(ab)
for name, address in ab.items():
    print 'Contact %s at %s' % (name, address)

if 'Guido' in ab: # OR ab.has_key('Guido')
    print " Guido's address is %s" % ab['Guido']