Python列表,元组,字典,序列,引用

1.列表

# Filename: using_list.py
# This is my shopping list
shoplist=["apple", "mango", "carrot", "banana"]
print ("I have", len(shoplist), "items to purchase.")
print ("These items are:"),
for item in shoplist:
  print (item),
print ("\nI 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 ("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)

2.元组

# !/usr/bin/python
# Filename: using_tuple.py

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])

3.元组打印

#!/usr/bin/python
# Filename: print_tuple.py
age = 22
name = 'Swaroop'
print ('%s is %d years old' % (name, age))
print ('Why is %s playing with that python?' % name)

4.字典

#!/usr/bin/python
# Filename: using_dict.py
# 'ab' is short for 'a'ddress'b'ook
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 ('\nThere are %d contacts in the address-book\n' % 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 ("\nGuido's address is %s" % ab['Guido'])

5.序列

#!/usr/bin/python
# Filename: seq.py
shoplist = ['apple', 'mango', 'carrot', 'banana']
# Indexing or 'Subscription' operation
print ('Item 0 is', shoplist[0])
print ('Item 1 is', shoplist[1])
print ('Item 2 is', shoplist[2])
print ('Item 3 is', shoplist[3])
print ('Item -1 is', shoplist[-1])
print ('Item -2 is', shoplist[-2])
# Slicing on a list
print ('Item 1 to 3 is', shoplist[1:3])
print ('Item 2 to end is', shoplist[2:])
print ('Item 1 to -1 is', shoplist[1:-1])
print ('Item start to end is', shoplist[:])
# Slicing on a string
name = 'swaroop'
print ('characters 1 to 3 is', name[1:3])
print ('characters 2 to end is', name[2:])

6.引用

#!/usr/bin/python
# Filename: reference.py
print ('Simple Assignment')
shoplist = ['apple', 'mango', 'carrot', 'banana']
mylist = shoplist # mylist is just another name pointing to the same object!
del shoplist[0]
print ('shoplist is', shoplist)
print ('mylist is', mylist)
# notice that both shoplist and mylist both print the same list without
# the 'apple' confirming that they point to the same object
print ('Copy by making a full slice')
mylist = shoplist[:] # make a copy by doing a full slice
del mylist[0] # remove first item
print ('shoplist is', shoplist)
print ('mylist is', mylist)
# notice that now the two lists are different

7.字符串

#!/usr/bin/python
# Filename: str_methods.py
name = 'Swaroop' # This is a string object
if name.startswith('Swa'):
    print ('Yes, the string starts with "Swa"')
if 'a' in name:
    print ('Yes, it contains the string "a"')
if name.find('war') != -1:
    print ('Yes, it contains the string "war"')
delimiter = '_*_'
mylist = ['Brazil', 'Russia', 'India', 'China']
print (delimiter.join(mylist))