search
HomeBackend DevelopmentPython TutorialBlack Horse Cloud Classroom 8 days of in-depth understanding of Python video materials

Python is an object-oriented, interpreted computer programming language invented by Guido van Rossum in 1989. The first public release was released in 1991. Python is purely free software. The source code and interpreter CPython follow the GPL (GNU General Public License) agreement. Python syntax is concise and clear, and one of its features is the mandatory use of white space as statement indentation. Python has rich and powerful libraries. It is often nicknamed the glue language, which can easily connect various modules made in other languages ​​​​(especially C/C++) together. "Black Horse Cloud Classroom 8-Day In-depth Understanding of Python Video Tutorial" will give you an in-depth understanding of the Python language.

Black Horse Cloud Classroom 8 days of in-depth understanding of Python video materials

Video playback address: http://www.php.cn/course/556.html

The difficulty of this video It lies in the call to C/C++:

1. Python calls the C dynamic link library


## Python calls the C library is relatively simple and is packaged into So, just use python's ctypes call.

(1) C language file: pycall.c

/***gcc -o libpycall.so -shared -fPIC pycall.c*/ #include #include

int foo(int a , int b)
{
printf("you input %d and %d\n", a, b);
return a+b;
}

(2) Gcc compiles and generates the dynamic library libpycall.so: gcc -o libpycall.so -shared -fPIC pycall.c. When using g++ to compile functions or methods in the code that generates C dynamic libraries, you need to use extern "C" for compilation.

(3) Python calls the file of the dynamic library: pycall.py

import ctypes
ll = ctypes.cdll.LoadLibrary
lib = ll("./libpycall.so")
lib.foo(1, 3)
print '***finish***'

(4) Running results:

2. Python calls C++( Class) dynamic link library

needs extern "C" to assist, which means that it can still only call C functions and cannot directly call methods, but it can parse C++ methods. Instead of using extern "C", the built dynamic link library does not have symbol tables for these functions.

(1) C++ class file: pycallclass.cpp

#include

using namespace std;

class TestLib
{
public:
void display();
void display(int a);
};
void TestLib::display() {
cout}

void TestLib::display(int a) {
cout}
extern "C" {
TestLib obj;
void display() {
obj.display();
void display_int() {
obj.display(2 );
} }
}


(2) g++ compiles and generates the dynamic library libpycall.so: g++ -o libpycallclass.so -shared -fPIC pycallclass.cpp.

(3) Python calls the file of the dynamic library: pycallclass.py


import ctypes

so = ctypes.cdll.LoadLibrary

lib = so("./ libpycallclass.so")
print 'display()' lib.display()
print 'display(100)' lib.display_int(100)


The teacher's lectures are relaxed and humorous, and the students Learn without stress. From the simple to the deep, from the deep to the simple, relaxed and cheerful is the overall image of this teacher.

The above is the detailed content of Black Horse Cloud Classroom 8 days of in-depth understanding of Python video materials. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
详细讲解Python之Seaborn(数据可视化)详细讲解Python之Seaborn(数据可视化)Apr 21, 2022 pm 06:08 PM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于Seaborn的相关问题,包括了数据可视化处理的散点图、折线图、条形图等等内容,下面一起来看一下,希望对大家有帮助。

详细了解Python进程池与进程锁详细了解Python进程池与进程锁May 10, 2022 pm 06:11 PM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于进程池与进程锁的相关问题,包括进程池的创建模块,进程池函数等等内容,下面一起来看一下,希望对大家有帮助。

Python自动化实践之筛选简历Python自动化实践之筛选简历Jun 07, 2022 pm 06:59 PM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于简历筛选的相关问题,包括了定义 ReadDoc 类用以读取 word 文件以及定义 search_word 函数用以筛选的相关内容,下面一起来看一下,希望对大家有帮助。

归纳总结Python标准库归纳总结Python标准库May 03, 2022 am 09:00 AM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于标准库总结的相关问题,下面一起来看一下,希望对大家有帮助。

分享10款高效的VSCode插件,总有一款能够惊艳到你!!分享10款高效的VSCode插件,总有一款能够惊艳到你!!Mar 09, 2021 am 10:15 AM

VS Code的确是一款非常热门、有强大用户基础的一款开发工具。本文给大家介绍一下10款高效、好用的插件,能够让原本单薄的VS Code如虎添翼,开发效率顿时提升到一个新的阶段。

Python数据类型详解之字符串、数字Python数据类型详解之字符串、数字Apr 27, 2022 pm 07:27 PM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于数据类型之字符串、数字的相关问题,下面一起来看一下,希望对大家有帮助。

详细介绍python的numpy模块详细介绍python的numpy模块May 19, 2022 am 11:43 AM

本篇文章给大家带来了关于Python的相关知识,其中主要介绍了关于numpy模块的相关问题,Numpy是Numerical Python extensions的缩写,字面意思是Python数值计算扩展,下面一起来看一下,希望对大家有帮助。

python中文是什么意思python中文是什么意思Jun 24, 2019 pm 02:22 PM

pythn的中文意思是巨蟒、蟒蛇。1989年圣诞节期间,Guido van Rossum在家闲的没事干,为了跟朋友庆祝圣诞节,决定发明一种全新的脚本语言。他很喜欢一个肥皂剧叫Monty Python,所以便把这门语言叫做python。

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

Repo: How To Revive Teammates
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

SublimeText3 English version

SublimeText3 English version

Recommended: Win version, supports code prompts!

Safe Exam Browser

Safe Exam Browser

Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

DVWA

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),