Tutorial by Examples: f

The matplotlib.animation package offer some classes for creating animations. FuncAnimation creates animations by repeatedly calling a function. Here we use a function animate() that changes the coordinates of a point on the graph of a sine function. import numpy as np import matplotlib.pyplot as p...

In this example we use the save method to save an Animation object using ImageMagick. import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation from matplotlib import rcParams # make sure the full paths for ImageMagick and ffmpeg are configured rcParams['ani...

This example will create an EC2 instance of t2.micro type in N.Virginia region running Amazon Linux. During the execution, it will ask to select the KeyPair to use and an I.P. CIDR from where you can SSH to the instance, use default to make SSH open to the internet { "AWSTemplateFormatVersion"...

To query a field which name is contained in a variable, use the field function. some_field = :id some_value = 10 from p in Post, where: field(p, ^some_field) == ^some_value

A good VOD (Video On Demand) service should start with the basics. Lets say you have a directory on your server that is not publicly accessible, yet through some sort of portal or paywall you want to allow users to access your media. var movie = path.resolve('./public/' + req.params.filename); ...

You can also use flent-ffmpeg to convert .mp4 files to .flv files, or other types: res.contentType('flv'); var pathToMovie = './public/' + req.params.filename; var proc = ffmpeg(pathToMovie) .preset('flashvideo') .on('end', function () { console.log(...

This writeup walks though steps to configure Tomcat to request CAC certificates from the client. It is focused on setting up a development environment, so some features that should be considered for production are not here. (For example it shows using a self-signed certificate for https and it does...

One implementation of the io.Reader interface can be found in the bytes package. It allows a byte slice to be used as the source for a Reader. In this example the byte slice is taken from a string, but is more likely to have been read from a file or network connection. message := []byte("Hello...

Sometimes it may be required to find out which directory consuming how much disk space especially when you are used df -h and realized your available disk space is low. du: du command summarizes disk usage of the set of FILEs, recursively for directories. It's often uses with -sh option: -s, --s...

You can define your own behaviour by adding -callback directives in your module. For example, if modules implementing your behaviour need to have a foo function that takes an integer and returns an atom: -module(my_behaviour). -callback foo(integer()) -> atom(). If you use this behaviour in...

In this iText 5 example, we'll create a text field and we'll add it to a PDF: public void manipulatePdf(String src, String dest) throws DocumentException, IOException { PdfReader reader = new PdfReader(src); PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest)); T...

In this iText 7 example, we'll create a text field and we'll add it to a PDF: public void manipulatePdf(String src, String dest) throws IOException { PdfReader reader = new PdfReader(src); PdfDocument pdf = new PdfDocument(reader, new PdfWriter(dest)); PdfAcroForm form = PdfAcroFor...

In this iText 5 example, we'll change the properties and the value of a text field: public void manipulatePdf(String src, String dest) throws DocumentException, IOException { PdfReader reader = new PdfReader(src); PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest)); ...

In this iText 7 example, we'll change the properties and the value of a text field: public void manipulatePdf(String src, String dest) throws IOException { PdfReader reader = new PdfReader(src); PdfDocument pdf = new PdfDocument(reader, new PdfWriter(dest)); PdfAcroForm form = PdfA...

To show you how work the views, we will assume that we want to query the document of type people. To do so, we will first need a design document that will hold our views. Note: for the purpose of the example, we will use many views inside of 1 design document. Therefore, in a production environment...

Rounding Values midway between two integers go toward the nearest even value. - round(4.5); val it = 4 : int - round(3.5); val it = 4 : int Truncation val it = 4 : int - trunc(4.5); val it = 4 : int - trunc(3.5); val it = 3 : int Floor and Ceiling - ceil(4.5); val it = 5 : int - f...

- real(6); val it = 6.0 : real

Instead of running intensive tasks into JavaFX Thread that should be done into a Service.So what basically is a Service? A Service is a class which is creating a new Thread every time you are starting it and is passing a Task to it to do some work.The Service can return or not a value. Below is ...

Case 1: While using in the place of method arguments. If a method requires an object of wrapper class as argument.Then interchangeably the argument can be passed a variable of the respective primitive type and vice versa. Example: int i; Integer j; void ex_method(Integer i)//Is a valid statem...

This is same as reading a manual for a command: man /path/to/man/file