1. 如果function不是None,等效于生成器表达式,比列表推导式省内存 2. 如果function是None,等效于列表推导式 f = filter(None,shares) # 函数为None,类似列表推导式,循环打印出每一个值 print(f,type(f)) #<filter object at 0x00000242A5C585C0> <class 'filter'> for i
res = sorted(dic, key=lambda k: dic[k][1], reverse=True)print(res) # 结果为:# ['owen', 'tom', 'zero'] # 1.与类型相关的 # list() str() ord() chr() bool() int() ... # 字符转ASCii码 print(ord('A'))# ASCII转对应字符 print(chr(97)) # 结果为: # 65 # a ASCI...
用于执行Python代码,object可以是string或代码对象。 execfile(filename[, globals[, locals ]]) 类似exec,执行文本。 file(name[, mode[, buffering ]]) 与open()类似,file类型的函数,见file objects。 filter(function, iterable) 过滤掉function中为false的部分,例子: def test(x): return (x > 3) filter...
Free variables are returned by locals() when it is called in function blocks, but not in class blocks. map() The map() function is used to execute a specified function for each item in a inerrable. max() The max() function is used to find the item with the largest value in an i...
sorted Built-in Function 相反,内置的sorted函数可以创造并返回一个新的list。其实sorted函数可接受任意的iterable object,包括不可变序列和生成器。 相同点 两者都只接受两个参数:reverse和key reverse : 如果为True,代表降序排列,默认为False key:一个只有一个参数的函数,这个函数会被用在序列里的每一个元素上,所...
Return a new list containing all items from the iterable in ascending order. A custom key function can be supplied to customize the sort order, and the reverse flag can be set to request the result in descending order. """ pass 1. ...
简介:Python编程:Built-in Functions内建函数小结 Built-in Functions(68个) 1、数学方法 abs() sum() pow() min() max() divmod() round() 2、进制转换 bin() oct() hex() 3、简单数据类型 - 整数:int() - 浮点数:float() - 字符\字符串:str() repr() ascii() ord() chr() format() ...
Excellent! Next, there is a function namedreverse()that – as the name suggests – reverses the order of elements in a list. Take a look: books = [ 'Sound of Steel', 'Silent Duty', 'Marked for Crime', 'Faceless Tribunal', 'Enemy of Evil', 'Shot for Gold', 'Beyond ...
sorted(iterable, cmp=None, key=None, reverse=False) # Python2 sorted(iterable, key=None, reverse=False) # Python3 参数: iterable:可迭代的对象 cmp:用于比较的函数 key:用来进行比较的元素 reverse:反转排序后的序列 返回值:返回重新排序的列表。 示例 print(sorted([10, 24, -180, 75])) # [-...
The reversed() function returns an iterator object that provides access to the elements of an iterable (list, tuple, string, etc.) in reverse order. Example string = 'Python' result = reversed(string) # convert the iterator to list and print it print(list(result)) # Output: ['n', '...