iOS on the use of dispatch_semaphore_t (semaphore_t) and dispatch_group_t (group) thread execution order

In 2017, looking back on the past, I devoted myself to iOS development in the first half of the year. In the second half of the year, I started python's long road, stopping and walking all the way, but fortunately, in general, 2017 is a year of harvest and effort. Come on in 2018! Turning back to the topic of thread execution, you may encounte ...

Posted on Thu, 03 Jan 2019 18:51:09 -0800 by stringman

Django Writes RESTful API (6): ViewSets and Routers

Welcome to my personal website: www.comingnext.cn Preface In this series of articles, when I wrote Django views in the first and second articles, I used a function-based approach, and each view function was preceded by a decorator @api_view with a django-rest-framework. Then in the third article, we started to change the function-based view t ...

Posted on Wed, 02 Jan 2019 23:24:10 -0800 by tsabar

PHP of MySQL implements WHERE&UPDATE&DELETE&LIKE&UNION.

WHERE You can use one or more tables in a query statement, commas and splits between tables. You can specify any condition in the WHERE clause One or more conditions can be specified using AND or OR The WHERE clause can also be applied to DETE or UPDATE commands in SQL Conditional queries using primary keys as WHERE clauses ...

Posted on Tue, 01 Jan 2019 20:06:09 -0800 by tripleaaa

shallow copy and deep copy in python

Today, when I write code, I encounter a wonderful problem. The problem is described as follows: The code declares a list, passes the list into function 1 () as a parameter, and del() the list in function 1 () removes an element. function2() also passes in a list as a parameter, and then calls function2() after calling function 1 (), there is a ...

Posted on Tue, 01 Jan 2019 12:18:07 -0800 by torvald_helmer

Long Way To Go Python 1

What is Python?   Dynamic Interpretative Strong Type Definition Language. (Understand the ball, slowly understand.... Programming languages have some subtypes: compiler and interpreter Static Language, Dynamic Language Strong Type Definition Language and Weak Type Definition Language      Compiler type: (C/C++) Complie: There is a program respo ...

Posted on Tue, 01 Jan 2019 00:27:08 -0800 by gilbertwang

< Translation > Python 3 Module of the Weekcd - -- Internet

Python 3 Module of the Weekcd--Internet Internet The Internet is a very popular field of modern computers. Even small, single-purpose scripts frequently interact with remote servers to send or receive data. Python provides a rich set of tools to handle Web protocols, so it is very suitable for writing Web-based applications (whether as clients ...

Posted on Thu, 27 Dec 2018 18:18:07 -0800 by bravo14

Python Data Grabbing & Analysis & Machine Learning & Mining & Neural Network

First: Data grabbing: 1: Background research 1: Check robots.txt to find out what restrictions are imposed on crawling the site. 2): pip install builtwith;pip install python-whois 2: Data grabbing: 1: Dynamic loading content: Using selenium #!/usr/bin/env python # -*- coding: utf-8 -*- from selenium import webdriver f ...

Posted on Thu, 27 Dec 2018 14:03:06 -0800 by t_miller_3

Python for Data Analysis v2 | Notes_ Chapter 3 Python Data Structure, Functions and Files

I use Sean Cheney series of special articles and original books as learning resources to record personal notes, which are only used for knowledge recording and later review. The address of the original author is checked. Sean Cheney If there are any mistakes, criticism and advice are also expected. -- ZJ Original Au ...

Posted on Wed, 26 Dec 2018 11:39:07 -0800 by aim25

Driver takes you to learn: Django+Xadmin to build an online education platform [Python 2& 3 Universal] (6) 1-3

6-1 Home Page and Login Page Configuration Users access our root directory, and we need to return html files to users. So the first step is to put the html file into the template directory. mark Find the HTML on the home page in html. Copy to our template directory mark New static Directory Used to store static files such as css, j ...

Posted on Tue, 25 Dec 2018 12:33:06 -0800 by kankaro

Learning Notes TF007:Tensor, Graph, Op, Variable, Placeholder, Session, Name Scope, Board Comprehensive Example

The input uses placeholders, the model receives arbitrary length vectors, calculates the total output of the data flow graph over time, divides the data flow graph reasonably by name scope, and saves the output, accumulation and mean of the data flow graph to disk at each run. [None] represents an arbitrary length vector and [] represents a sca ...

Posted on Sat, 22 Dec 2018 08:48:05 -0800 by drag0ner