# class Toy: # head='blue' # body='blue' # def a(): # print('class internal function') # toy1=Toy() # print(toy1) # Toy.a() # class Toy: # '''this is a toy class''' # head='blue' # body='blue' # def a(self): # print('class internal function') # def __init_(self, leg): # self.leg=leg # toy1=Toy(2) # print(Toy.__dict__) # print(toy1.__dict__) # print(toy1.a) #Toy.a # print(toy1.a()) #Toy.a(toy1) # toy1.x=10 # print(toy1.__dict__) # toy2=Toy(4) # print(toy2.__dict__) #How python store data? # #case 1 string look like identifier # a='hello' # b='hello' # print(id(a)) # print(id(b)) # #case 3 long string but look like identifier # a='hello_world' # b='hello_world' # print(id(a)) # print(id(b)) # #case 4 # a='_this_is_a _long_string_that_could_be_used_as_an_identifier' # b='_this_is_a _long_string_that_could_be_used_as_an_identifier' # print(id(a)) # print(id(b)) # #case 5 # a='1_hello_world' # b='1 hello world' # print(id(a)) # print(id(b)) # #case 6 not interned # a='1 hello world' # b='1 hello world' # print(id(a)) # print(id(b)) # #case 7 interning strings # a='this _is _a_long_string' # b='this _is _a_long_string' # print('a==b:', a==b) # print('a is b:', a is b) # #8 can't use is # a='hello world' # b='hello world' # print('a==b:', a==b) # print('a is b:', a is b) # #9 force intern a, b must be set intern # import sys # a=sys.intern('hello world') # b=sys.intern('hello world') # c='hello world' # print(id(a)) # print(id(b)) # print(id(c)) # #case 10 compare speed # def compare_using_equals(n): # a=sys.intern('a long string that is not interned' * 200) # b=sys.intern('a long string that is not interned' * 200) # for i in range(n): # if a==b: # pass # def compare_using_interning(n): # a=sys.intern('a long string that is not interned' * 200) # b=sys.intern('a long string that is not interned' * 200) # for i in range(n): # if a is b: # pass # import time # start=time.perf_counter() # compare_using_equals(10000000) # end=time.perf_counter() # print('equality: ', end-start) # start=time.perf_counter() # compare_using_interning(10000000) # end=time.perf_counter() # print('interning: ', end-start) ############################################## #Star-Argument # def a(x, *arg): # print('Hello World!', x, arg) # a(1,2,3,4,5,6) # def a(x,y, *arg): # print('Hello World!', x, y, arg) # def b(h,i): # print(h,i) # b(arg[0],arg[1]) # a(1,2,3,4,5,6) #------------------------------------------------ # def a(x,y=1, *arg): # print('Hello World!', x, y, arg) # def b(h,i): # print(h,i) # b(arg[0], arg[1]) # a(1,2,3,4,5,6) #------------------------------------------------- # def a(x,y,z): # print('a={1}, b={0}, c={2}'. format(x,y,z)) # a(1,2,3) #-------------------------------------------------- # def a(x,y=2,z=3): # print('a={1}, b={0}, c={2}'. format(x,y,z)) # a(1,2,3) #keyword argument----------------------------------- # def a(x,z, y=2): # print('a={1}, b={0}, c={2}'. format(x,y,z)) # a(1,2,3) #---------------------------------------------------- # def a(x,*arg, z=1, **kwarg): # print(x, arg, kwarg) # a(1,2,3,4,z,y=6) # ans: 1(2,3.4) {'z':3, 'y':6} #---------------------------------------------------- # def a(x,*arg, z=4, **kwarg): # print(x, z,arg, kwarg) # a(1,2,3,4,z=3,y=6) # print(globals()) # #globals for scan all variable and value in function # print(a.__str__) #ans:1 3 (2, 3, 4) {'y': 6} #------------------------------------------------------ def a(x,*arg, z=4, **kwarg): print(x, z,arg, kwarg) file(__name__=='__main__'): #for make sure the location of file while running a(1,2,3,4,z=3,y=6) print(globals()) #globals for scan all variable and value in function print(a.__str__, a.__name__) #a