15分でPythonのやり方を知ることができます.201800523

# Python       ‘#’
""" Python     
      """,      
      ，      。
"""

#               ， Python            
2.0  #      
11.0 / 4.0  #         2.75 ！      ？ 

#   ‘//’     ，python3           .
5 // 3   # => 1
5.0 // 3.0 # => 1.0 
-5 // 3  # => -2
-5.0 // 3.0 # => -2.0


from __future__ import division #        __future__     
                                #  python2   python3   
11/4    # => 2.75  ...     
11//4   # => 2 ...     

#      
7 % 3 # => 1

#     2 4  
2**4 # => 16

#    ，   ，    
(1 + 3) * 2  # => 8

#      
#  ：or   and             
True and False #=>   False
False or True #=>   True

#          ，  0 ，     
0 and 2 #=> 0
-5 or 0 #=> -5
0 == False #=> True
2 == True #=> False
1 == True #=> True

#  not   
not True  # => False
not False  # => True

#     “==”，      True ，     False
1 == 1  # => True
2 == 1  # => False

#     “！=”，          True，    Flase
1 != 1  # => False
2 != 1  # => True

#   /           
1 < 10  # => True
1 > 10  # => False
2 <= 2  # => True
2 >= 2  # => True

# Python             ，
       #        False，    False
1 < 2 < 3  # => True
2 < 3 < 2  # => False

#      "    '      
"This is a string."
'This is also a string.'

#          +      ，       ？
"Hello " + "world!"  # => "Hello world!"
#      '+' ，           
"Hello " "world!"  # => "Hello world!"

 #     *  ，        ，   ；
         importantNote = "        
" * 3 
         print （importantNote）
        """    ：
                 
                 
                 
        """

"Hello" * 3  # => "HelloHelloHello"

#              
"This is a string"[0]  # => 'T'

#       %  ，          
       #（ C/C++   %d     ，%s     ，
       # python        ，           ）
x = 'apple'
y = 'lemon'
z = "The items in the basket are %s and %s" % (x,y)

#                  .format()  ，       
"{} is a {}".format("This", "placeholder")
"{0} can be {1}".format("strings", "formatted")
# You can use keywords if you don't want to count.
"{name} wants to eat {food}".format(name="Bob", food="lasagna")

# None     ,None  None，         
None  # => None

#   None     ，   “==”   ，  “is”
"etc" is None  # => False
None is None  # => True


#“is"            ，
        #           
#    “is”，          ， “is”     
# bool             
#          
#   - None
#   -       0 (e.g., 0, 0L, 0.0, 0j)
#   -    、    (e.g., '', (), [])
#   -    、    (e.g., {}, set())
#   -       ：
#     https://docs.python.org/2/reference/datamodel.html#object.__nonzero__
#
# All other values are truthy (using the bool() function on them returns True).
bool(0)  # => False
bool("")  # => False

# if           ,         “  ‘yahool’  3  2  ，    2“
"yahoo!" if 3 > 2 else 2  # => "yahoo!"

# python      
li = []
#                
other_li = [4, 5, 6]

# append           
li.append(1)    # li is now [1]
li.append(2)    # li is now [1, 2]
li.append(4)    # li is now [1, 2, 4]
li.append(3)    # li is now [1, 2, 4, 3]
# pop         
li.pop()        # => 3 and li is now [1, 2, 4]
#      append  
li.append(3)    # li is now [1, 2, 4, 3] again.

#   []                
       #（  ，index       ）
li[0]  # => 1
#      []            
li[0] = 42
li[0]  # => 42
#   []       ，             
li[-1]  # => 3

#              ，    。
#     insert()     ，                 
li[4]  # Raises an IndexError

#     [:],           
# (It's a closed/open range for you mathy types.)
#        ，  li[1:3],      index 1、2    ，
#             []     
li[1:3]  # => [2, 4]
#        ，          。
li[2:]  # => [4, 3]
li[:3]  # => [1, 2, 4]

# [::2]     [0]  ，   2   
li[::2]   # =>[1, 4]
# [::-1]      ，-          ， 1    ，  1            
li[::-1]   # => [3, 4, 2, 1]
# []         [  ：  ：  ]
# li[start:end:step]

#  "del"              
del li[2]   # li is now [1, 2, 3]

#     “+”          , ：     +   ，   （set） +   -
li + other_li   # => [1, 2, 3, 4, 5, 6]


#     "extend()"         
li.extend(other_li)   # Now li is [1, 2, 3, 4, 5, 6]

# Remove     del   ， remove      ，   index
li.remove(2)  # li is now [1, 3, 4, 5, 6]
li.remove(2)  #   remove        ，    

#          ，      ，  index     ，        
li.insert(1, 2)  # li is now [1, 2, 3, 4, 5, 6] again

#       index
li.index(2)  # => 1
li.index(7)  #   

# "in"                 
1 in li   # => True

# "len()"           
len(li)   # => 6

# Tuples(  ）            ，          
tup = (1, 2, 3)
tup[0]   # => 1
tup[0] = 3  #        

#              （     ）
len(tup)   # => 3
tup + (4, 5, 6)   # => (1, 2, 3, 4, 5, 6)
tup[:2]   # => (1, 2)
2 in tup   # => True

#            
a, b, c = (1, 2, 3)  # a  1，b 2，c 3
d, e, f = 4, 5, 6      #            
#                
g = 4, 5, 6          # => (4, 5, 6)
# Python          ：            
e, d = d, e  # d is now 5 and e is now 4

# Python      
empty_dict = {}
#              
filled_dict = {"one": 1, "two": 2, "three": 3}

#     [] key         
filled_dict["one"]   # => 1

#     "keys()"          key 
filled_dict.keys()   # => ["three", "two", "one"]
# Note -    keys           .
#                 

#    "values()"             ，
 #                   
filled_dict.values()   # => [3, 2, 1]


#      "in"                 ，       
"one" in filled_dict   # => True
1 in filled_dict   # => False

#       key  ，Python   
filled_dict["four"]   # KeyError

#  "get()"              
filled_dict.get("one")   # => 1
filled_dict.get("four")   # => None
#          ，get           ，
#              
filled_dict.get("one", 4)   # => 1
filled_dict.get("four", 4)   # => 4


#               ，  []      
filled_dict["four"] = 4  # now, filled_dict["four"] => 4

# "setdefault()"          
#     ：              ，setdefault（）     
filled_dict.setdefault("five", 5)  # filled_dict["five"] is set to 5
filled_dict.setdefault("five", 6)  # filled_dict["five"] is still 5

empty_set = set()
#    set        set()   
some_set = set([1, 2, 2, 3, 4])   # some_set is now set([1, 2, 3, 4])

#          ！         ！         ！
another_set = set([4, 3, 2, 2, 1])  # another_set is now set([1, 2, 3, 4])

# Python2.7  ，{}         
filled_set = {1, 2, 2, 3, 4}   # => {1, 2, 3, 4}

# Add           
filled_set.add(5)   # filled_set is now {1, 2, 3, 4, 5}

#      &      
other_set = {3, 4, 5, 6}
filled_set & other_set   # => {3, 4, 5}

#   |      
filled_set | other_set   # => {1, 2, 3, 4, 5, 6}

#    -       
{1, 2, 3, 4} - {2, 3, 5}   # => {1, 4}

#    ^       
{1, 2, 3, 4} ^ {2, 3, 5}  # => {1, 4, 5}

#    >=                 
{1, 2} >= {1, 2, 3} # => False

#    <=                
{1, 2} <= {1, 2, 3} # => True

#    in             
2 in filled_set   # => True
10 in filled_set   # => False

"""
      for...in...      ：
    dog is a mammal
    cat is a mammal
    mouse is a mammal
"""
for animal in ["dog", "cat", "mouse"]:
    # You can use {0} to interpolate formatted strings. (See above.)
    print "{0} is a mammal".format(animal)

"""
  "range()"   ，  for     
prints:
    0
    1
    2
    3
"""
for i in range(4):
    print i

"""
"range(lower, upper)"    lower   upper  ,
   ：range          
prints:
    4
    5
    6
    7
"""
for i in range(4, 8):
    print i

"""
while   
prints:
    0
    1
    2
    3
"""
x = 0
while x < 4:
    print x
    x += 1  # Shorthand for x = x + 1

# Python   try/except   

# Python2.6     ，  try...except...:
try:
    # raise       。     raise  ，raise          。
    raise IndexError("This is an index error")
except IndexError as e:
    pass    # pass    ，    
except (TypeError, NameError):
    pass    # python           
else:   # Python         ，           
    print "All good!"   
finally: #  finally           
    print "We can clean up resources here"

#  with  ，    try....except...    [with  ](http://www.ibm.com/developerworks/cn/opensource/os-cn-pythonwith/)
with open("myfile.txt") as f:
    for line in f:
        print line

# Python        
#          *        
def varargs(*args):
    return args

varargs(1, 2, 3)   # => (1, 2, 3)

#     **     Key              

def keyword_args(**kwargs):
    return kwargs

#       **     ，Python           
keyword_args(big="foot", loch="ness")   # => {"big": "foot", "loch": "ness"}


#             ，      ：
def all_the_args(*args, **kwargs):
    print args
    print kwargs
"""
all_the_args(1, 2, a=3, b=4) prints:
    (1, 2)
    {"a": 3, "b": 4}
"""

#       ，      ，      ，    ：
args = (1, 2, 3, 4)
kwargs = {"a": 3, "b": 4}
all_the_args(*args)   # equivalent to foo(1, 2, 3, 4)
all_the_args(**kwargs)   # equivalent to foo(a=3, b=4)
all_the_args(*args, **kwargs)   # equivalent to foo(1, 2, 3, 4, a=3, b=4)

#              *    **   ，        
def pass_all_the_args(*args, **kwargs):
    all_the_args(*args, **kwargs)
    print varargs(*args)
    print keyword_args(**kwargs)

#      X
x = 5

def set_x(num):
    #            ，     gloabl   ，         
    x = num # => 43
    print x # => 43

def set_global_x(num):
    global x
    print x # => 5
    x = num #   global    ，            
    print x # => 6

set_x(43)
set_global_x(6)

#             /*    ，    */
def create_adder(x):
    def adder(y):
        return x + y
    return adder

add_10 = create_adder(10)
add_10(3)   # => 13

# Lambda           
(lambda x: x > 2)(3)   # => True 
(lambda x, y: x ** 2 + y ** 2)(2, 1) # => 5

# map              
map(add_10, [1, 2, 3])   # => [11, 12, 13]
map(max, [1, 2, 3], [4, 2, 1])   # => [4, 2, 3]

filter(lambda x: x > 5, [3, 4, 5, 6, 7])   # => [6, 7]

#              ，       ：
#add_10(i)     for...in...      ，         。
[add_10(i) for i in [1, 2, 3]]  # => [11, 12, 13]
[x for x in [3, 4, 5, 6, 7] if x > 5]   # => [6, 7]

 #    
 species = "H. sapiens"   
             __species = "Other.sapiens" #    ，         

 # __init__(),     ，python         ，        ，
 #             ，               ，    ：   
 #__init__      ，        
 # __del__       ，       
 #__repr__   ，  
 #__setitem__      
 #__getitem__       
 #__len__    
 #__cmp__    
 #__call__    
 #__add__   
 #__sub__   
 #__mul__   
 #__div__   
 #__mod__    
 #__pow__  

 def __init__(self, name):
     #       ，    ，         
     #         
     self.name = name
     self.age = 0

 #            self       
 #（               ）
 def say(self, msg):
     return "{0}: {1}".format(self.name, msg)

 #    
 @classmethod
 def get_species(cls):
     return cls.species

 #     ，
 @staticmethod
 def grunt():
     return "*grunt*"

 # A property is just like a getter.
 # It turns the method age() into an read-only attribute
 # of the same name.
 #property  ，   getter
 @property
 def age(self):
     return self._age

 # This allows the property to be set
 @age.setter
 def age(self, age):
     self._age = age

 # This allows the property to be deleted
 @age.deleter
 def age(self):
     del self._age

#python       
import math
dir(math)

# If you have a Python script named math.py in the same
# folder as your current script, the file math.py will 
# be loaded instead of the built-in Python module. 
# This happens because the local folder has priority
# over Python's built-in libraries. 

#            Python       math.py
#      math.py       Python  
#   Python                    

#    wraps，wraps    
# Beg will call say. If say_please is True then it will change the returned
# message
from functools import wraps

def beg(target_function):
    @wraps(target_function)
    def wrapper(*args, **kwargs):
        msg, say_please = target_function(*args, **kwargs)
        if say_please:
            return "{} {}".format(msg, "Please! I am poor :(")
        return msg

    return wrapper

@beg