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CURL alternative in Python. Tentative_NumPy_Tutorial - SciPy wiki dump. Please do not hesitate to click the edit button. You will need to create a User Account first. Before reading this tutorial you should know a bit of Python. If you would like to refresh your memory, take a look at the Python tutorial. If you wish to work the examples in this tutorial, you must also have some software installed on your computer. These you may find useful: ipython is an enhanced interactive Python shell which is very convenient for exploring NumPy's features matplotlib will enable you to plot graphics SciPy provides a lot of scientific routines that work on top of NumPy NumPy's main object is the homogeneous multidimensional array.

For example, the coordinates of a point in 3D space [1, 2, 1] is an array of rank 1, because it has one axis. Numpy's array class is called ndarray. Ndarray.ndim the number of axes (dimensions) of the array. Ndarray.shape the dimensions of the array. Ndarray.size the total number of elements of the array. Ndarray.dtype ndarray.itemsize ndarray.data Note. 9 OpenCV tutorials to detect and recognize hand gestures – Into Robotics. The interaction between humans and robots constantly evolve and adopt different tools and software to increase the comfort of humans. In this article, I explore nine tutorials that show you different methods to detect and recognize hand gestures. The OpenCV library is not enough to start your project. This library provides you the software side, but you also need hardware components. In the hardware category enters a developed platform able to run the OpenCV library, webcams, and 3D sensors such as Kinect 3D.

The OpenCV is a free and open-source library focused on real-time image processing. It can detect and recognize a large variety of objects, but our focus now is to apply techniques and methods to detect and recognize the gestures of a human hand. Methods to detect the gestures of a hand As you can see in the following tutorials, there are several methods to detect the hand gestures. Another method doesn’t use the color hand; it uses the convexity detection of OpenCV. 11 Online Learning websites to learn how to code and more! Planning start something new in this year? You can start to learn online now.

Online education is gaining popularity over the last few years, as it should. I have tried few of them last year and will share my experience with them in this post. Since I am a software developer we are going to focus on the materials related to it. So, here is a list of sites that you should visit before you make you make your choice. The italic text below the title are taken from the respective sites. Editor’s Note: The list is continuously updated as more sites come live and as some of them get closed down 1. Kick-start your programming projects We recently made the content publicly and freely available, so that it can reach and help out more people. JCG Courses 2. We’re the world’s online learning marketplace, where 8 million+ students are taking courses in everything from programming to yoga to photography–and much, much more.

Udemy Grab the deal NOW! 3. Skillshare 4. Achieve your dreams and change the world. SQL: Inner vs Outer Joins. Joins are used to combine the data from two tables, with the result being a new, temporary table. The temporary table is created based on column(s) that the two tables share, which represent meaningful column(s) of comparison. The goal is to extract meaningful data from the resulting temporary table. Joins are performed based on something called a predicate, which specifies the condition to use in order to perform a join.

A join can be either an inner join or an outer join, depending on how one wants the resulting table to look. It is best to illustrate the differences between inner and outer joins by use of an example. It’s important to note that the very last row in the Employee table does not exist in the Employee Location table. Outer Joins Let’s start the explanation with outer joins. Subscribe to our newsletter for more free interview questions. In this SQL we are joining on the condition that the employee ID’s match in the rows tables. Inner Joins This can also be written as: ProgressBar Control. A progress bar is a control that an application can use to indicate the progress of a lengthy operation such as calculating a complex result, downloading a large file from the Web etc.

ProgressBar controls are used whenever an operation takes more than a short period of time. The Maximum and Minimum properties define the range of values to represent the progress of a task. Minimum : Sets the lower value for the range of valid values for progress. Maximum : Sets the upper value for the range of valid values for progress. Value : This property obtains or sets the current level of progress. By default, Minimum and Maximum are set to 0 and 100. The following C# program shows a simple operation in a progressbar . Progress Bars, Threads, Windows Forms, and You. Introduction Has your program ever locked up while it was performing a lengthy operation? Have you ever wondered how to implement a nice jazzy progress bar to prove to your end user that the program hasn't crashed?

Have you experimented in the past with ProgressBars and found yourself unbelievably frustrated trying to get them to work properly? If you answered "yes" to any of the questions above, don't worry - you are not alone. Anyone who has worked with Visual X.NET has pulled their hair out in rage trying to get some piece of their program to work properly at some time in their programming career. This article will help address the concerns about one of those pieces - the progress bar. This article assumes a basic understanding about how Windows Forms are created in Visual Studio, specifically how to create a form, put a button on the form, and attach an event to that button. A Note About Progress Bars Here are some situations when a progress bar would be appropriate: Getting Started.

Using the DropDownList and ListBox with ASP.NET MVC in C# for Visual Studio 2010. Getting Started with ASP.NET MVC 5 | The ASP.NET Site. This tutorial will teach you the basics of building an ASP.NET MVC 5 web app using Visual Studio 2013. Download the completed project. This tutorial was written by Scott Guthrie (twitter@scottgu ), Scott Hanselman (twitter: @shanselman ), and Rick Anderson ( @RickAndMSFT ) You need an Azure account to deploy this app to Azure: You can open an Azure account for free - You get credits you can use to try out paid Azure services, and even after they're used up you can keep the account and use free Azure services.You can activate MSDN subscriber benefits - Your MSDN subscription gives you credits every month that you can use for paid Azure services. Getting Started Start by installing and running Visual Studio Express 2013 for Web or Visual Studio 2013.

Visual Studio is an IDE, or integrated development environment. Creating Your First Application Click New Project, then select Visual C# on the left, then Web and then select ASP.NET Web Application. Click F5 to start debugging. How to use the IComparable and IComparer interfaces in Visual C# This step-by-step article describes the use of two interfaces: IComparer and IComparable. These interfaces are discussed in the same article for two reasons. These interfaces are frequently used together, and although the interfaces are similar (and have similar names), they serve different purposes. If you have an array of types (such as string or integer) that already support IComparer, you can sort that array without providing any explicit reference to IComparer. In that case, the elements of the array are cast to the default implementation of IComparer (Comparer.Default) for you. However, if you want to provide sorting or comparison capability for your custom objects, you must implement either or both of these interfaces.

The following .NET Framework Class Library namespace is referenced in this article: System.Collections IComparable The role of IComparable is to provide a method of comparing two objects of a particular type. IComparer Using IComparer is a two-step process. Lambda Expressions (C# Programming Guide) A lambda expression is an anonymous function that you can use to create delegates or expression tree types. By using lambda expressions, you can write local functions that can be passed as arguments or returned as the value of function calls.

Lambda expressions are particularly helpful for writing LINQ query expressions. delegate int del(int i); static void Main(string[] args) { del myDelegate = x => x * x; int j = myDelegate(5); //j = 25 } To create an expression tree type: using System.Linq.Expressions; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { Expression<del> myET = x => x * x; } } } The => operator has the same precedence as assignment (=) and is right-associative. In the previous example, notice that the delegate signature has one implicitly-typed input parameter of type int, and returns an int. (input parameters) => expression The parentheses are optional only if the lambda has one input parameter; otherwise they are required. Reference Concepts. C# Best Practices - Dangers of Violating SOLID Principles in C# As the process of writing software has evolved from the theoretical realm into a true engineering discipline, a number of principles have emerged.

And when I say principle, I’m referring to a feature of the computer code that helps maintain the value of that code. Pattern refers to a common code scenario, whether good or bad. For example, you might value computer code that works safely in a multi-threaded environment. You may value computer code that doesn’t crash when you modify code in another location. Indeed, you might value many helpful qualities in your computer code, but encounter the opposite on a daily basis. There have been some fantastic software development principles captured under the SOLID acronym—Single responsibility, Open for extension and closed for modification, Liskov substitution, Interface segregation, and Dependency injection. The SOLID acronym and the principles encompassed within did not originate with me. The Single Responsibility Principle What’s wrong here? Threading in C# - Free E-book. Threading in C# Joseph Albahari Last updated: 2011-4-27 Translations: Chinese | Czech | Persian | Russian | Japanese Download PDF Part 1: Getting Started C# supports parallel execution of code through multithreading.

A C# client program (Console, WPF, or Windows Forms) starts in a single thread created automatically by the CLR and operating system (the “main” thread), and is made multithreaded by creating additional threads. All examples assume the following namespaces are imported: using System; using System.Threading; class ThreadTest{ static void Main() { Thread t = new Thread (WriteY); t.Start(); for (int i = 0; i < 1000; i++) Console.Write ("x"); } static void WriteY() { for (int i = 0; i < 1000; i++) Console.Write ("y"); }} The main thread creates a new thread t on which it runs a method that repeatedly prints the character “y”.

Once started, a thread’s IsAlive property returns true, until the point where the thread ends. Done static void Go(){ if (! Done Done (usually!) Join and Sleep. 24 Websites to Keep Your Finger on the Pulse in Web Development. Image via Flickr/dav On your journey to becoming a front-end web developer, you don’t have to go it alone. Resources abound online for everything from keeping up to speed on industry news and finding high-quality jobs to interacting with other developers, learning new key skills, and keeping those skills sharpened. Bonus: many of said resources are totally free. If you’re in it to win it, bookmark this toolkit of 24 online tools for front-end web developers. NEWS: Keep up with industry trends and developments DailyJS: This site offers daily JavaScript news and tutorials in a simple, highly readable format.HTML5Weekly: Those in the know sign up for this free weekly Wednesday newsletter, a curated selection of news about HTML5 and other web platform technology.

JOBS: Find high-quality front-end dev gigs Hired: Hired is an online marketplace created specifically for engineers, data scientists, designers, and product managers. NETWORKING: Interact with other developers Want even more? The 5 Best Websites To Learn Python Programming. Over the past decade, the Python programming language has exploded in popularity amongst programmers in all areas of coding. From web developers to video game designers to in-house tool creators, many people have fallen in love with the language. Why? Because it’s easy to learn, easy to use, and very powerful. If you’re looking to pick up Python, you’re in luck. There are lots of web resources to learn python, and many of them are entirely free. Here are some of the best ones. For optimal results, we recommend that you utilize ALL of these websites as they each have their own great aspects. #1 – How To Think Like A Computer Scientist The most notable aspect of this web Python tutorial series is that not only does it teach you how to use the Python programming language, but it teaches you how to think like programmers think.

Keep in mind, however, that learning how to think like a computer scientist will require a complete shift in your mental paradigm. . #2 – Dive Into Python #4 – TryPython. Python. Raspberry Pi. Learn PHP Programming. Getting started with Embedded Linux: Part Five. JSON. Processing.js. Processing Quick Start | Processing.js. Processing.js Quick Start - Processing Developer Edition Introduction This quick start guide is written from the standpoint of a Processing developer. No HTML or JavaScript knowledge is assumed, and only basic Processing knowledge is necessary. Index For the Impatient If you're in a rush, here's what you need to know: Processing.js is written in JavaScript, and uses HTML5's <canvas> element. 1 <script src="processing-1.0.0.min.js"></script>2 <canvas data-processing-sources="hello-web.pde"></canvas> Load your web page, and it will parse, translate, and run your sketch in the browser.

Why Processing.js? The Web: from Java to JavaScript Processing is built using Java. In the end, Java became an important server side technology, receding from the client-side and browser. Processing.js uses Modern Web Standards Processing.js is built using JavaScript and HTML5. Processing.js automatically converts your Processing code to JavaScript. Here's a sample of a Processing.js sketch running in the browser.