Flutter learning note 04: Dart data type

One of the most basic characteristics of programming language is the data types it supports. These are the types of values that can be represented and manipulated in programming languages. The Dart language supports the following types: 1. Number int, double 2. String 3. bool 4. List (similar to array) ...

Posted on Sat, 06 Jun 2020 00:07:34 -0700 by msandersen

xpath of Python 3 crawler

1, Introduction XPath is a language for finding information in XML documents. XPath can be used to traverse elements and attributes in an XML document. XPath is the main element of the W3C's XSLT standard, and XQuery and XPointer are built on top of XPath expressions. 2, Installation pip3 install lxml 3, Use Select node Common path expressions ...

Posted on Fri, 05 Jun 2020 20:15:25 -0700 by BinaryDragon

PySide2 basic chapter: QPushButton application

PySide2 basic part (3) - QPushButton application preface:What can I learn from reading this article?                         . ——If you think this is a good blog, I ...

Posted on Thu, 04 Jun 2020 23:34:31 -0700 by Michael_zz

python's requests library and beutifusoup library crawling girls' pictures

1: python crawler - using requests library to get information of web page Record your reptile process In fact, I want to use jsonpath and json before climbing, and then I found that after opening the Meitu bar website, I only thought about the methods of crawling the requests library and the beautifu ...

Posted on Thu, 04 Jun 2020 08:39:09 -0700 by Jay87

Numpy Foundation (novice come quickly!)

NumPy is a scientific computing library that provides python with high-performance vectors, matrices and high-dimensional data structures. It is realized by C and Fortran, so it has a very good performance to establish equations by vector and matrix and realize numerical calculation. NumPy is basical ...

Posted on Thu, 04 Jun 2020 07:43:47 -0700 by wildmanmatt

Python 3 remote Linux server executes commands and uploads and downloads files

1, Introduction Paramiko is based on SSH to connect to the remote server and perform relevant operations (SSHClient and SFTPClinet, i.e. remote connection, upload and download service). The module can be used to command or operate files on the remote server. It is worth mentioning that the internal remote management of fabric and ansible is rea ...

Posted on Wed, 03 Jun 2020 07:20:10 -0700 by joe1986

Python:Python reference counting guide in memory

Yunqi information:[ Click to see more industry information]Here you can find the first-hand cloud information of different industries. What are you waiting for? Come on! This article will introduce you to Python reference counting and the use of variable list objects in the demonstration, but it will not introduce the details of C language im ...

Posted on Sun, 31 May 2020 23:50:20 -0700 by Scott_J

Day 58: getting started with Web development Django

by Aurora Today, I'd like to introduce Django, another web development framework of Python. It is an open-source Web application framework customized based on python. It originated from an online news web site at first, and then opened up in 2005. Django has large and comprehensive functions. It provides a one-stop solution, which allows devel ...

Posted on Sun, 31 May 2020 23:11:44 -0700 by captainplanet17

Automatic test: Selenium automatically logs in and authorizes, and then Requests the content

Selenium automatically logs in to the website, screenshots and Requests to capture the content of the webpage after login. Let's get to know each other. Selenium: a comprehensive project of a series of tools and libraries supporting Web browser automation. Requests: the only non transgenic Python HTTP library, which can be safely enjoyed by ...

Posted on Sun, 31 May 2020 18:01:20 -0700 by plapeyre

Use Python to draw your own personal footprint map, accurate to the city level

preface The text and pictures of this article are from the Internet, only for learning and communication, not for any commercial purpose. The copyright belongs to the original author. If you have any questions, please contact us in time for handling. Add Penguin Group 695185429 and you can get it for free. All the information is in the group fi ...

Posted on Sun, 31 May 2020 02:08:36 -0700 by Leesa