3-python automated self

Time:
    the time_format = "% D%% Y-X-M-%" --- Set time format
    time_current = time.strftime (time_format) ---- time format using

higher-order function:
    Variable parameters can point function, the function can be receive variables, a function that can receive another function as a parameter, this function is called to order function
            , for example:
                ABS (-10) 10 --- --- built-in functions, negative to positive stresses
                    def add (a, B, D)
                        return F (a) + F (B)
                    the Add (. 3, -6, ABS)
anonymous functions:
    anonymous function is no explicit specified function
, for example: calc = lambda n: n ** n

function definition:
    DEF funtion ():
        .........

parameters:
    arguments: actually present in memory
    parameter: actually exists, but after running function will disappear
    
    positional parameters: def test (x, y) --- characteristics: parameter correspondence with
    a keyword parameters: test (y = 1, x = 2) ---- features: parameter independent of the order (as long as it must be changed to match)
    The default parameters: def test (y, x = 1, y = 2) ---- Features: delivery time can be overridden
    
    Note: The
        keyword parameter is not written in the front position parameters, or will be error
        when the parameters passed only can correspond to a location, can not have multiple positions at a time to pass a parameter value
        loaded manner not change before dictionary keyword parameters, time parameters can be accepted but the
    parameter group:
        (. 1) Test DEF (X, * args)
            DEF test (* args) ---- features: you can accept multiple arguments and put inside a tuple,
                for example:
                    by value: test (1,23,4,5)
                    transmission list: test (* [1,2 , 34,5])
        (2) Test DEF (** kwargs) ---- features: the N-th keyword stored parameters into a dictionary
                for example:
                    transfer value: test (name = 'chenming' , age = 9) --- ways to write keywords
                    transfer dictionary: test (** { 'name' : 'chen', 'age': 8})
                references:
                    kwargs [ 'name'] --- display value

return value return:
    The return value can be a tuple: example: return 1, 'hello', [ 'wo', 'ni'], { 'name': 'chen'}
    return value can be a value of None
    Return Value can be a boject
    
local variable :
    that is, in a certain range which affect certain parameters, such as the function declaration of
    local variables are global variables can not be changed, but only strings and integers
global variables:
    the impact of global variables, global
    
recursion:
    the concept: use time continue to enter when the inner layer is not going to return results to the total after the call is completed, the results returned from the inside out, maximum 998 recursive
    characteristics
        must have a clear end variables,
        recursive efficiency is not high, too many levels of recursion can cause a stack overflow
        each time deeper into the recursive problem size should be reduced compared to the previous recursive
functional programming:
    functional programming function of this term does not refer to the computer's function (actually Subroutine), but learning index the function, i.e., the argument map. That value is only a function of the value determined in the function parameters, independent of other state. For example sqrt (x) function calculates the square root of x, as long as the same x, whenever called, calling times, the value is constant
    , for example:
        var Subtract Result = (Multiply (the Add (1,2),. 3), 4);

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Origin www.cnblogs.com/chenming-1998/p/11717296.html