Conditional Statement

>>>
>>> if ( age < 15 ): print("1")
... else print("2)
  File "<stdin>", line 2
    else print("2)
             ^
SyntaxError: invalid syntax
>>> if ( age < 15 ):
...     print(1)
... else:
...     print(2)
...
2


>>> if ( age < 15 ):
...     print("y")
... else:
...     print("NNN")
...
y
>>>

注意排版

Tuples

>>> tup
('aaa', 'bbb', 222, 333, 'eee')
>>> tup2 = ( 11, 222, 333, 'dddd', "eeeee" )

>>> tup
('aaa', 'bbb', 222, 333, 'eee')
>>> tup2
(11, 222, 333, 'dddd', 'eeeee')
>>> tup3 = tup + tup2
>>> tup3
('aaa', 'bbb', 222, 333, 'eee', 11, 222, 333, 'dddd', 'eeeee')
>>> tup3[2:5]
(222, 333, 'eee')
>>> tup3 = tup + tup * 3
>>> tup3
('aaa', 'bbb', 222, 333, 'eee', 'aaa', 'bbb', 222, 333, 'eee', 'aaa', 'bbb', 222, 333, 'eee', 'aaa', 'bbb', 222, 333, 'eee')
>>> len(tup3)
20
>>> del tup3
>>>

Dictionaries

>>> students = { "aaa":11, 'bbb':12, 'ccc':13 }
>>> students
{'aaa': 11, 'bbb': 12, 'ccc': 13}
>>> students['bbb']
12
>>>

>>> students
{'aaa': 11, 'bbb': 12, 'ccc': 13}
>>> students['ccc'] = 33
>>> students
{'aaa': 11, 'bbb': 12, 'ccc': 33}
>>>

Lists ( Array )

>>> list_a = [ "aaa", "bbb", "ccc", 'dddd' ]
>>> list_a
['aaa', 'bbb', 'ccc', 'dddd']
>>>

>>> list_a[1:2]
['bbb']
>>> list_a[0:2]
['aaa', 'bbb']
>>>


>>> list_a
['aaa', 'bbb', 'ccc', 'dddd']
>>> list_a[0] = 0
>>> list_a
[0, 'bbb', 'ccc', 'dddd']
>>>



>>> del list_a[1]
>>> list_a
[0, 'ccc', 'dddd']
>>>



>>> list_b = [ 'b0', "b1", 2 ]
>>> list_b
['b0', 'b1', 2]
>>>

>>> list_b.append(4)
>>> list_b
['b0', 'b1', 2, 4]
>>>







>>> list_a
[0, 'ccc', 'dddd']
>>> list_b
['b0', 'b1', 2, 4]
>>> list_a + list_b
[0, 'ccc', 'dddd', 'b0', 'b1', 2, 4]
>>> list_a + list_b * 2
[0, 'ccc', 'dddd', 'b0', 'b1', 2, 4, 'b0', 'b1', 2, 4]
>>>
>>> max(list_a)
'dddd'
>>> min(list_b)
2

Placeholders

>>> sent = "%s is %d years old."
>>> sent%("John",  13)
'John is 13 years old.'

>>> sent
'%s is %d years old.'
>>>


>>>
>>> sent2 = sent%("Ali", 40 )
>>> sent2
'Ali is 40 years old.'
>>>

Arithmetic Operators

first_name = "first"
last_name = "last"

• first_name + " " + last_name ==> "first last"

• first_name * 3  ==> "firstfirstfirst"
• first_name[0]  ==> 'f'

sa = "1234567890abcdef"

• sa[0:3]   ===>  "123"
• sa[:3]   ===> "123"
• sa[:-5]   ===> "1234567890a"
• sa[5:6]   =====> "6"
• sa[5:7]   =====> "67"

Variables and Multiple Assignment

• age = 20x
• sentence = "My name is xxxx"
• Tom, Bob, Sandy = 15, 18, 22
• Mike = Enya = 18