Developers must see | devweekly issue 1: what is time complexity?

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Open source project

1. pikepdf

PythonStar:1.4k

pikepdf Is a for reading and writing PDF Of documents Python library .

It's based on QPDF, and QPDF Is a powerful PDF Operation and repair Library .

This library is similar to PyPDF2 and pdfrw, however , Compared with the latter two , It provides richer PDF Operation function , And allow for existing PDF Editing and content conversion .

It has many excellent characteristics , for example ：

• Edit and transform PDF
• And Jupyter and IPython Notebook integration , Achieve rapid development
• PDF encryption
• Support from the 1.1 To 1.7 All versions of PDF file
• modify PDF/A Without destroying PDF/A Compliance with
• Automatically fix those with internal errors PDF file

2. towhee

PythonStar:721

Towhee It's a flexible 、 Application oriented framework , adopt ML Workflow of models and other operations to generate embedded vectors .

Its purpose is to make x2vec More convenient 、 Easy to use , From junior developers to large organizations – It only takes a few lines of code to generate dense embedding.

In order to achieve this goal , It provides pre built workflows for various tasks , Including audio / Music embedding 、 Image embedding 、 Character recognition and so on .

3. ga-extractor

PythonStar:31

ga-extractor It's a CLI Tools , It can use Google reports API Extract Google Analytics data , It can also be used to convert data into various formats suitable for migration to other analysis platforms .

4. envelope

PythonStar:146

How to use Python Code to automatically send mail ？ If you add additional information or attachments through code ？

envelope Just one line of code , You can send email / Signature / Add a message and attachment in the process of encrypting content .

Insert a message and attachment , And send an email through a single line / Signature / Encrypted content .

It's in python-gnupg、M2Crypto、smtplib、magic And e-mail processing package on the basis of a layer of packaging , Their multiple functions are combined into a single function .

Here is an example code ：

Envelope("my message")
    .subject("hello world")
    .to("[email protected]")
    .attach(file_contents, name="attached-file.txt")
    .smtp("localhost", 587, "user", "pass", "starttls")
    .signature()
    .send()

5. FairEmail

JavaStar:942

A full-featured 、 Open source 、 Privacy conscious Android email application

FairEmail It's easy to set up , And it can be compatible with almost all e-mail systems , Include Gmail、Outlook and Yahoo!

however , It pays more attention to privacy , If you want to develop your own email that pays more attention to privacy APP,FairEmail Very useful .

It has the following characteristics ：

• The function is all ready
• 100％ Open source
• Privacy oriented
• Unlimited account
• Unlimited email addresses
• Unified inbox （ You can choose an account or folder ）
• Two way synchronization
• Push notification
• Offline storage and operation
• Low flow consumption
• small (~25 MB)
• concise

6. Camera

JavaStar:361

Camera It is a modern camera that pays attention to privacy and security APP, Can scan QR And barcodes

It's new GrapheneOS Camera applications , be based on Android Of CameraX library .

7. dns.toys

GoStar:1.8k

One DNS The server , adopt DNS The agreement provides useful tools and services .

for example , The weather 、 World time 、 Unit conversion, etc

It provides convenient utilities and services , It can be easily accessed from the command line .

Here are some sample commands ：

dig help @dns.toys

dig mumbai.time @dns.toys

dig newyork.weather @dns.toys

dig 42km-mi.unit @dns.toys

dig 100USD-INR.fx @dns.toys

dig ip @dns.toys

dig 987654321.words @dns.toys

dig pi @dns.toys

dig 100dec-hex.base @dns.toys

8. vrperfkit

CStar:513

a VR Performance toolbox , Performance oriented VR game mods aggregate .

Include mods：

• Upgrade technology （ Render at a lower resolution and upgrade to the target resolution ）
• AMD FidelityFX Super resolution
• NVIDIA image zoom
• AMD Contrast adaptive sharpening
• Fixed depression rendering
• Variable rate coloring

besides , It also supports Oculus、OpenVR these VR Operating environment and Direct3D 11 graphics API.

9. Hacker-Typer

JavaScriptStar:672

Hacker-Typer Is a simple web side gadget , Simulate hacker typing , It looks cool .

You can open the page and tap the keyboard at will , It will generate a cool piece of code .

10. ceresdb

RustStar:1.3k

CeresDB It's a high performance 、 Distributed 、Schema-less Cloud native time series database , Be able to handle sequential types at the same time （time-series） And analytical （analytics） load .

Tool resources

1. RegExr

RegExr It's based on HTML/JS Tools for , Used to create 、 Test and learn regular expressions .

2. BrainIDE

BrainIDE Designed to provide an easy to use 、 Lightweight and user friendly IDE.

It's all used python and tkinter Conduct GUI Design and code .

The main purpose of this software is to do without Internet connection , Brainstorm coding during the journey .

3. Geany

Geany It is a small and light integrated development environment . Its development is to provide a small and fast integrated development environment , It only needs to rely on other software packages .

Another goal is to be as independent as possible from things like KDE or GNOME Such a special desktop environment .

therefore , It only uses GTK+ tool kit , So you just need GTK+ Runtime to run Geany.

4. Lorien

Lorien It's a canvas / painting / Note taking app , Focus on performance 、 Small save files and simplicity .

It is not like Krita、Gimp or Photoshop That's based on bitmap images , Instead, the strokes are saved as a collection of points , And render them at runtime （ It's kind of like SVG）.

It is mainly designed as a digital notebook and brainstorming tool .

5. Shortcut

Shortcut It's free of charge 、 Cross platform 、 Open source video editing tool .

Technical articles

1. What is time complexity ？

In the process of software development , Time complexity 、 Spatial complexity is often used to analyze the complexity of data structures and algorithms .

In computer science , How to find out which algorithm or data structure is more effective or faster ？ How can we compare two algorithms or data structures ？

We can compare a given algorithm by time complexity ： An algorithm that completes a given task faster is better .

This article describes in detail what is time complexity ？ And how to understand time complexity ？

2. How the VS Code Run in C++？

If you do Python Development , Choose the interpreter 、IDE、 Configuring the environment is a very simple job , You just need to install Python That's all right. .

however , When processing C++ when , This time becomes much more complicated , Because it needs a compiler , There are many C++ Compiler available .

This article uses MinGW Based on , Share some good tools , These tools will make the running process of the program easier .