principal component analysis example python

This example describes the Python class inheritance usage. Share to everyone for your reference. The specific method is as follows: #!/usr/bin/python # Filename:inherit.py Class Schoolmember: ' represents any school member. ' def __init__ (self, Name, age): Self.name = name Self.age = Age print ' (initialized Schoolmember:%s) '% Self.nam E def tell (sel

This example describes the use of the __call__ method in Python and shares it for everyone's reference. The specific methods are analyzed as follows: __call__ in Python allows programmers to create callable objects (instances), by default the __call__ () method is not implemented, which means that most instances are not callable. However, if this method is overr

An example of script maintenance is a bit messy, just as an instance, demonstrating how to quickly use the tool to quickly achieve the goal:Application: shell and python data interaction, data capturing, and Code Conversion Copy codeThe Code is as follows:# Coding: UTF-8#! /Usr/bin/python'''Program Description: apache access. log analysisAnalyze the source of the

Python decorator example use analysisOverview The decorator is essentially a Python function that allows other functions to add additional functions without any code changes. The return value of the decorator is also a function object. We need a decorator that can test the function running time, which can be defined as follows: def timer(func): def wrapper(*ar

This article mainly introduces the usage of python function parameters and describes in detail the functions, definitions, and usage skills of Python function parameters, for more information about how to use python function parameters, see the following example. Share it with you for your reference. The details are as

In this paper, the binary search algorithm of Python is analyzed. Share to everyone for your reference. The specific analysis is as follows: Today, when reading books, the book mentions that the dichotomy of the law, although the truth is simple, we can understand that the real one-time to write the implementation of the error is still relatively difficult, even if you have enough hours, such as 1 hours. I

The examples in this article describe Python dynamic parameter usage. Share to everyone for your reference. The specific analysis is as follows: Take a look at the code first: Class Person: def __init__ (self,*pros,**attrs): self.name = "Jeff" Self.pros = Pros for (Key,value) in Attrs.items (): stm = "self.%s =/"%s/""% (key,value) exec (STM) if __name__ = = "__main__":

This article mainly introduces the example of using the modifier in Python programming, including decorative functions and methods, parameter-included decorators and decorative classes. For more information, see Decoration functions and methods We first define two simple mathematical functions, one for calculating the sum of squares and the other for calculating the square difference: # get square sumdef

This article mainly introduces the comparison between Lambda and def usage in Python, and analyzes the difference between Lambda and def and the use of it, which has a certain reference value, and the need for friends can refer to This paper compares and analyzes the usage of lambda and def in Python. Share to everyone for your reference. The specific analysis

In this paper, the method of realizing the algorithm of the Markov chain by Python is described. Share to everyone for your reference. The specific analysis is as follows: In the "Programming Practice" (English name "The Practice of Programming") of the book, the third chapter of the C language, C++,awk and Perl respectively, the implementation of the MA-fu chain algorithm, to enter through the text, "ran

The examples in this article describe the use of enumerate functions in Python. Share to everyone for your reference. The specific analysis is as follows: A new function enumerate is found today. In general, when you want to traverse an index and traverse an element for a list or array, you write: For I in range (0,len (list)): print I, List[i] But this method is a bit cumbersome, using the built-in

This example describes the use of sleep functions in Python. Share to everyone for your reference. Specific as follows: Sleep in Python is used to pause thread execution in seconds #-----------------------------------# name:sleep.py# author:kevin harris# last modified:02/13/04# Description:this Python sc

This article mainly introduces the Python list parsing operation, combined with instance form to analyze the Python list for integer, character and matrix parsing operation implementation skills, the need for friends can refer to the following The example in this article describes the list parsing operation for Python

This article mainly introduced the Python recursive function definition and usage, combined with the concrete instance form to analyze the Python recursive function principle, the realization technique and the related attention matters, the need friend can refer to the next This article describes the Python recursive function definition and usage. Share to every

This article mainly introduces the RSA encryption/decryption and signature/verification functions implemented under Python, and analyzes the implementation method of RSA encryption and decryption in Python, and the use of signature and verification function, which can be referenced by a friend. This article describes the RSA encryption/decryption and signature/verification functions implemented under

This example describes the python function parameter usage. Share to everyone for your reference. Specific as follows: Function parameters: The arguments that the function takes are the values that you provide to the function so that the function can do something with these values. These parameters are like variables, except that their values are defined when we call the function, not within the function

**2print (Square_sum (3, 4 )) Print (Square_diff (3, 4)) The pre_str above is an adorner that allows parameters. It is actually a function encapsulation of the original adorner and returns an adorner. We can interpret it as a closure with environmental parameters. When we invoke @pre_str (' ^_^ '), Python can discover this layer of encapsulation and pass parameters to the adorner's environment. The call is equivalent to: Square_sum = Pre_str (' ^_^ '

In this article, we'll look at python os.chdir, and in the next article we'll introduce the Os.chdir () in Python, which describes its definition and its role and purpose. Overview The Os.chdir () method is used to change the current working directory to the specified path. Grammar The syntax format for the ChDir () method is as follows: Os.chdir (PATH) Parameters Path-the new path to switch to.

This example describes the use of random modules in Python. Share to everyone for your reference. Specifically as follows: ? 1 2 3 4 Import random x = Random.randint (1,4); y = Random.choice ([' Appale ', ' banana ', ' cherry ', ' durian ']); Print (x,y); The results of the operation are as follows: (2, ' cherry ') No matter which language I study, I always like to get a random

In this paper, we describe the method of Python backtracking to realize the output of array in full order. Share to everyone for your reference. The specific analysis is as follows: Full permutation explanation: any m (m≤n) elements from n different elements, arranged in a certain order, are called an arrangement of extracting m elements from n different elements. All permutations are called when m=n.