一:all和any
all和any 如果是空可迭代对象(字符串,列表,字典,元祖),返回True 里面传入的是可迭代对象,(字符串,列表,字典,元祖)可迭代对象里面不能是空,如果是空,返回False
1 all和any # print(all(['sb',0])) # print(all([])) # print(all(())) # print(all({})) # print(all('')) # print(any(['',1],)) # # 里面传入的是可迭代对象,(字符串,列表,字典,元祖)可迭代对象里面不能是空,如果是空,返回False # 如果是空可迭代对象(字符串,列表,字典,元祖),返回True 2 # 输入字符串返回编码位置 # print(ord('我')) 3 # 输入一个编码位置,返回字符串 # print(chr(25105)) 4 # repr 返回里面是什么就是什么,必须跟着可迭代对象 原形毕露 # %r # print(repr('[alex]')) # name='alex%r'%('_sb') # print(name) 5 # slice 有返回值,可设置起始值 切片 # l=[1,2,3,4] # print(slice(1,l[1::])) # slice # l1 = [11,22,33,44] # print(l1[1::2]) # sl = slice(1,4,2) # print(l1[sl]) 6 # reversed('我是可迭代对象,返回迭代器') l2=reversed(l1) # l1 = [11,33,22,44,'alex'] # # l1.reverse() # # print(l1) # l2=reversed(l1) # print(l2) # for i in reversed(l1): # print(i) 7 # dic = {'k1':20,'k2':30,'k3':100} # def func(x): # return dic[x] # l1 = max(dic,key=func,) # print(l1) # dic = {3:20,2:30,1:100} # def func(x): # return x # l1 = max(dic,key=func,) # print(l1) # 8 # zip拉链 将可迭代对象最少的为基准,可放多个对象,一一对应,返回一个元祖 # from collections import Iterator # l1 = [1,2,3,4,5] # l2 = ['wusir','alex','taibai'] # l3 = ['*',"**"] # print(zip(l1,l2)) # print(isinstance(zip(l1,l2),Iterator)) # for i in zip(l1,l2,l3): # print(i)
9 #map #[i*i for i in range(5)] # print([i*i for i in range(5)]) # print(map(abs,[1,2,3,-4,-5,-7])) # for i in map(abs,[1,2,3,-4,-5,-7]): # print(i) # def func(x):return x*x # for i in map(func,range(5)): # print(i) # def func(x):return x*x # for i in map(func,[0,1,2,3,4]): # print(i) 10 #filter 过滤 # [i for i in [1,2,3,4,5] if i % 2 == 0] # def func1(x):return x % 2 == 0 # for i in filter(func1,[1,2,3,4,5]): # print(i) 11 #sorted 返回的是列表 #形成一个新列表,并返回 #与list.sort() 改变原列表 # l1 = [1,4,3,5,7,8] # print(sorted(l1,)) # print(l1) # l = ['fsdafsa','fddsaf','qqq','fgasjdlg;dsjfg'] # # def func1(x): # # return len(x) # # for i in sorted(l,key=func1): # # print(i) # print(sorted(l,key=len))