principal component analysis example python

The examples in this article describe how Python sorts lists. Share to everyone for your reference. The specific analysis is as follows: 1, sort () function The sort () function sorts the list using a fixed sort algorithm. The sort () function changes the list as it is sorted so that the elements in the list are ordered in a certain order, rather than simply returning a sorted copy of the list. Note that

In this paper, the method of implementing the Markov chain algorithm in Python is described. Share to everyone for your reference. The specific analysis is as follows: In the book "The Practice of Programming" (English name "The Practice of Programming"), the third chapter, respectively, uses the C language, C++,awk and Perl respectively to implement the horse-ear-chain algorithm to generate some useful te

This example describes the Python insertion sorting algorithm. Share to everyone for your reference. Specific as follows: def insertsort (array): for Removed_index in range (1, len (array)): removed_value = Array[removed_index] Insert_index = Removed_index while insert_index > 0 and Array[insert_index-1] > removed_value: array[inse Rt_index] = array[insert_index-1] insert_index

The example of this paper describes the Python network programming, share to everyone for your reference. Here's how: The service-side code is as follows: From Socketserver import (TCPServer as TCP, Streamrequesthandler as SRH) from time import ctime HOST = ' PORT = 21 567 ADDR = (HOST, PORT) class Myrequesthandle (SRH): def handle (self): print ' connecting from. ', Self.client_add Re

This article describes the Python probabilistic Calculator implementation method. Share to everyone for your reference. The implementation method is as follows: From the random import randrange#randrange form random moduledef Calc_prob (strengths): "" "A function that receives an array o F. Numbers indicating the strength of each party and returns the winner "" "If Strengths[1]>strengths[0]: #Bring The bigger number to the first position in the array

This example describes the Python stack class. Share to everyone for your reference. Specifically as follows:? 1 2 3 4, 5 6 7 8 9 10 11 12 13 14 15 Class Path: #a list used like a stack def __init__ (self): self. P = [] def push (self,t): self. P.append (t) def pop (self): return self. P.pop () def top (self): return self. P[-1] def remove (self): self. P.pop (0) def isempty (self): return (

This article describes the Replace method in Python in the form of an instance, which is very useful, as follows: There are two main types of replace methods: Last_date = "1/2/3" target is "123" Method One: Repalce Date =last_date.replace ('/', ') Method Two: RE p = re.compile ("/") date = P.sub (", last_date) Note that you must not escape, or the function will not take effect. The Replace method returns a copy of the

This example describes the Python builder generator usage. Share to everyone for your reference. Specific as follows: With yield, you can let a function generate a result sequence, not just a value For example: def countdown (n): print "Counting" while n>0: yield n #生成一个n值 Next () calls the generator function to run until the next yield statement,

This example describes the Python probability calculator implementation. Share to everyone for your reference. The implementation method is as follows: From random import randrange #randrange form random Module def calc_prob (strengths): "" "A function that receives A arr Ay of two numbers indicating the strength of each party and returns the winner "" "If Strengths[1]>strengths[0]: #Bring the bigger

This article mainly introduces the use of Python callback function, the more detailed analysis of the commonly used invocation methods, and examples of the Python callback function using skills, the need for friends can refer to the There is always a certain interface between software modules, from the way of invocation, they can be divided into three categories

format of the Time.asctime (), and by default the Time.time () is passed as a parameter. Time.gmtime (): Converts a timestamp to utc+0 time zone (China should be + 8 time zone, 8 hours apart), and will default to Time.time () as a parameter. Time.strftime (Format,time.localtime ()): Converts a time tuple to a formatted time character, without giving the time tuple argument the default to pass Time.localtime () as a parameter For example, th

In this article we are going to go into details about Regular ExpressionsAdvanced knowledge, and I'll come up with some of the problems that might arise in Python programming. examples of regular expressions. First advanced point of knowledge: Slicing a string Using regular expressions to slice a string is more flexible than a fixed character, see the normal segmentation code: >>> ' a B c '. Split (') [' A ', ' B ', ', ' ', ' C '] Well, you can't

,count))0x03 Precautions ① encountered in the course of execution: ' GBK ' codec can ' t decode byte 0x82 in position 20:illegal multibyte sequence coding error: Content = Open ("C:\\user S\\geek\\desktop\\python.txt "," R ", encoding= ' Utf-8 ')Here is the TXT file i downloaded "kingdoms" is ASCII, how to do it! After the search learned that to normal operation will have to change the TXT encoding to UTF-8 form to run successfully, how to do it!First: Open txt text → file → Save As → encode →u

The examples in this article describe the Python daemon usage. Share to everyone for your reference. The specific analysis is as follows: The daemon can run all the time without blocking the main program from exiting. To flag a daemon, you can set the Daemon property of the process instance to true. The code is as follows: ? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Import OS import

This example describes the Python builder generator usage. Share to everyone for your reference. Specifically as follows: With yield, you can have a function generate a sequence of results, not just a value For example: ? 1 2 3 4 5 6 7 8 9 10 11 12-13 def countdown (n): print "Counting Down" while N>0:yield n #生成一个n值 n-=1 >>> C = Countdown (5)

The example in this article describes the Python class inheritance usage. Share to everyone for your reference. Specifically as follows: ? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26-27--28 29---30 31--32 33 34 35 36 37 38-39 40 41 42 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 5 86 87 Help (

This example describes how to use the Python singleton pattern. Share to everyone for your reference. Specifically as follows: Method One Copy Code code as follows: Import threading Class Singleton (object): __instance = None __lock = Threading. Lock () # Used to synchronize code def __init__ (self): "Disable the __init__ method" @staticmethod Def getinstance (): If not singleton