Python 入門 - その２

• Python : http://www.python.org/

• MacBook% cd lorepos/svn/elmarverde/lang/python/introductory/

• Hello Python!
  • tuple : イミュータブル
  • list : ミュータブル
  • 参考 => イミュータブル - Wikipedia
    • MacBook% vim collection2.py

#!/usr/bin/env python 3


# get length
print (len*1 # answer : 6
print (len("purposefully")) # answer : 12


x = ["cat", 77, -333, "Ryu", 123]
# y = ("dog", 55, -111, "Day", 789)


x.append("Good")
# y.append("Bad") # answer : process down here


print (x) # answer : ['cat', 77, -333, 'Ryu', 123, 'Good']
# print (y)

• • • MacBook% python collection.py

1
6
12
['cat', 77, -333, 'Ryu', 123, 'Good']

• • • MacBook% python3 collection.py

1
6
12
['cat', 77, -333, 'Ryu', 123, 'Good']

• • • MacBook% vim collection2.py

#!/usr/bin/env python 3


# get length
print (len*2 # answer : 6
print (len("purposefully")) # answer : 12


x = ["cat", 77, -333, "Ryu", 123]
y = ("dog", 55, -111, "Day", 789)


x.append("Good")
y.append("Bad") # answer : process down here


print (x) # answer : ['cat', 77, -333, 'Ryu', 123, 'Good']
# print (y)

• • • MacBook% python collection.py

1
6
12
Traceback (most recent call last):
File "collection2.py", line 12, in
y.append("Bad") # answer : process down here
AttributeError: 'tuple' object has no attribute 'append'

• • • MacBook% python3 collection.py

1
6
12
Traceback (most recent call last):
File "collection2.py", line 12, in
y.append("Bad") # answer : process down here
AttributeError: 'tuple' object has no attribute 'append'

• エラー理由 : 'tuple' object has no attribute 'append'
  • 補足 : y が tuple が イミュータブル だから

*1:"two",))) # answer : 1 print (len([9, 8, 7, 6, "kuma", 5]

*2:"two",))) # answer : 1 print (len([9, 8, 7, 6, "kuma", 5]