Tutorial by Examples: a

Why do we need to relax all the edges at most (V-1) times

To understand this example, it is recommended to have a brief idea on Bellman-Ford single source shortest path algorithm which can be found here In Bellman-Ford algorithm, to find out the shortest path, we need to relax all the edges of the graph. This process is repeated at most (V-1) times, where...

algorithm • Bellman–Ford Algorithm

Write one log file per day

Create one log file for each day. The log files will have the following names (dependent of culture) 2016-06-05.log 2016-06-06.log 2016-06-07.log ... <?xml version="1.0" ?> <nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://w...

nlog • Write logs to files

Create custom Target

using NLog; using NLog.Config; using NLog.Targets; namespace MyNamespace { [Target("MyFirst")] public sealed class MyFirstTarget: TargetWithLayout //or inherit from Target { public MyFirstTarget() { //set defaults ...

nlog • Extending NLog

Create custom Layout Renderer

[LayoutRenderer("hello-world")] public class HelloWorldLayoutRenderer : LayoutRenderer { /// <summary> /// I'm option and not required or default /// </summary> public string Config1 { get; set; } /// <summary> /// I'm required option. ...

nlog • Extending NLog

Detecting Negative Cycle in a Graph

To understand this example, it is recommended to have a brief idea about Bellman-Ford algorithm which can be found here Using Bellman-Ford algorithm, we can detect if there is a negative cycle in our graph. We know that, to find out the shortest path, we need to relax all the edges of the graph (V-...

algorithm • Bellman–Ford Algorithm

declare weakly typed variables

declare is an internal command of bash. (internal command use help for displaying "manpage"). It is used to show and define variables or show function bodies. Syntax: declare [options] [name[=value]]... # options are used to define # an integer declare -i myInteger declare -i another...

Bash • Typing variables

Installation or Setup

This would be a basic setup in wich we will send all the log messages to the console and to a log file. Let's start with the libraries. Will use maven for that: <dependency> <groupId>org.apache.logging.log4j</groupId> <artifactId>log4j-api</artifact...

log4j2 • Getting started with log4j2

Web Page Using Materializecss

Here is an example of a basic page using the Materialize CSS framework which incorporates the grid system and materialboxed. <!DOCTYPE html> <html> <head> <title>Materializecss Example webpage</title>  <link href="ht...

materializecss • Getting started with materializecss

Storing Graphs (Adjacency List)

Adjacency list is a collection of unordered lists used to represent a finite graph. Each list describes the set of neighbors of a vertex in a graph. It takes less memory to store graphs. Let's see a graph, and its adjacency matrix: Now we create a list using these values. This is called adjacen...

algorithm • Graph

Two-way conversions

Descriptor objects can allow related object attributes to react to changes automatically. Suppose we want to model an oscillator with a given frequency (in Hertz) and period (in seconds). When we update the frequency we want the period to update, and when we update the period we want the frequency ...

Python Language • Descriptor

Deref implementation for Option and wrapper structure

use std::ops::Deref; use std::fmt::Debug; #[derive(Debug)] struct RichOption<T>(Option<T>); // wrapper struct impl<T> Deref for RichOption<T> { type Target = Option<T>; // Our wrapper struct will coerce into Option fn deref(&self) -> &Option...

Rust • Auto-dereferencing

Simple Deref example

Deref has a simple rule: if you have a type T and it implements Deref<Target=F>, then &T coerces to &F, compiler will repeat this as many times as needed to get F, for example: fn f(x: &str) -> &str { x } fn main() { // Compiler will coerce &&&&&&a...

Rust • Auto-dereferencing

Solving a univariate inequality

>>> from sympy.solvers.inequalities import solve_univariate_inequality >>> from sympy import var >>> x=var('x') >>> solve_univariate_inequality(2*x**2-6>1,x,relational=False) (-oo, -sqrt(14)/2) U (sqrt(14)/2, oo) The relational=False parameter simply ind...

sympy • Solvers

All Pair Shortest Path Algorithm

Floyd-Warshall's algorithm is for finding shortest paths in a weighted graph with positive or negative edge weights. A single execution of the algorithm will find the lengths (summed weights) of the shortest paths between all pair of vertices. With a little variation, it can print the shortest path ...

algorithm • Floyd-Warshall Algorithm

Minimal: Log a message

// 1.0, Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { /** * User Event 1.0 example detailing usage of the Submit events * * @appliedtorecord employee */ var exports = {}; function beforeSubmit(type)...

netsuite • User Event: Before and After Submit events

Before Submit: Validate record before it is committed to database

For this example, we want to make sure that any Employee who is marked as a Project Resource also has an appropriate Labor Cost defined. // 1.0, Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { /** * User Event 1.0 example detailing...

netsuite • User Event: Before and After Submit events

After Submit: Determine whether a field was changed

After the record gets stored in the database, we want to inspect what was changed on the record. We'll do this inspection by comparing values between the old and new record instances. // 1.0, Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { ...

netsuite • User Event: Before and After Submit events

Restrict execution based on the action that triggered the User Event

// 1.0 // Utilize the type argument and raw Strings to filter your // execution by the action function beforeLoad(type, form, request) { // Don't do anything on APPROVE // Note that `type` is an Object, so we must use ==, not === if (type == "approve") { return...

netsuite • User Event: Before Load event

Restrict execution based on the context that triggered the User Event

In SuiteScript 1.0, we retrieve the current execution context using nlapiGetContext().getExecutionContext(), then we compare the result to the appropriate raw Strings. // 1.0 in Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { var exports =...

netsuite • User Event: Before Load event

Reading a String from Standard Input

The STDIN stream in Julia refers to standard input. This can represent either user input, for interactive command-line programs, or input from a file or pipeline that has been redirected into the program. The readline function, when not provided any arguments, will read data from STDIN until a newl...

Julia Language • Input