Tutorial by Examples: er

Insert Data in nedb

Basically, in order to insert records to nedb, the data is stored in the form of json with the key being the column names and the value for those names will be the values for that record. var rec = { name: 'bigbounty',age:16}; db.insert(rec, function (err, newrec) { // Callback is optional ...

electron • Using nedb in electron

Set yarn as default package manager for @angular/cli

Yarn is an alternative for npm, the default package manager on @angular/cli. If you want to use yarn as package manager for @angular/cli follow this steps: Requirements yarn (npm install --global yarn or see the installation page) @angular/cli (npm install -g @angular/cli or yarn global add @an...

Angular 2 • Angular-cli

Calculating power in O(log n)

This example shows an efficient way of calculating power using template metaprogramming. template <int base, unsigned int exponent> struct power { static const int halfvalue = power<base, exponent / 2>::value; static const int value = halfvalue * halfvalue * power<base, e...

C++ • Arithmitic Metaprogramming

Containers

.container has one fixed width for each screen size in bootstrap (xs,sm,md,lg); .container-fluid expands to fill the available width. @media (min-width: 568px) { .container { width: 550px; } } @media (min-width: 992px) { .container { width: 970px; } } @media (min-width: 1...

twitter-bootstrap • Bootstrap Containers

Type Inference

Acknowledgement This example is adapted from this article on type inference What is type Inference? Type Inference is the mechanism that allows the compiler to deduce what types are used and where. This mechanism is based on an algorithm often called “Hindley-Milner” or “HM”. See below some of th...

F# • Types

Connect DataSource from external API

Please me mindful of importing all necessary libraries required. This example uses InMemoryDbService from angular-in-memory-web-api to provide the JSON data from mock API. Live demo service.ts: import { Injectable } from '@angular/core'; import { Headers, Http } from '@angular/http'; import...

angular-material2 • md-table

Supervised Learning

The machine learns to predict an output when given an input. Each training case consists of an input and a target output. Regression The target ouput takes continuous values. Predicting the price of a stock Predicting a house price Classification The target output is a class label. Wha...

machine-learning • Types of learning

Unsupervised Learning

Unsupervised learning allows us to approach problems with little or no idea what our results should look like. We can derive structure from data where we don't necessarily know the effect of the variables. The most common type of unsupervised learning is cluster analysis or clustering. It is the ta...

machine-learning • Types of learning

Apply Filter to Image Patches and Set Each Pixel as the Mean of the Result of Each Patch

Many modern Image Processing algorithms use patches are their basic element to work on. For instance one could denoise patches (See BM3D Algorithm). Yet when building the image form the processed patches we have many results for the same pixel. One way to deal with it is taking the average (Empir...

MATLAB Language • Usage of `accumarray()` Function

Consider we are connecting MYSQL RDS with your rails application.

Steps to create MYSQL database Login to amazon account and select RDS service Select Launch DB Instance from the instance tab By defaul MYSQL Community Edition will be selected, hence click the select button Select the database purpose, say production and click next step Provide the mysql ver...

Ruby on Rails • Adding an Amazon RDS to your rails application

Simple HttpClient AuthToken Interceptor (Angular 4.3+)

import { Injectable } from '@angular/core'; import { HttpEvent, HttpHandler, HttpInterceptor, HttpRequest } from '@angular/common/http'; import { UserService } from '../services/user.service'; import { Observable } from 'rxjs/Observable'; @Injectable() export class AuthHeaderInterceptor imple...

Angular 2 • Http Interceptor

Place the user's pin in the map.

Note, if you are not familiar with the google maps api, you may read the precedent example (basics) in order to understand this little example. First, initialize the map. You may add an map's element in your HTML code and a bite of CSS like this: <!DOCTYPE html> <html> <h...

google-maps-api-3 • Getting started with google-maps-api-3

Faster multiplication or division by powers of 2

Shifting bits left (right) is equivalent to multiplying (dividing) by 2. It's the same in base 10: if we "left-shift" 13 by 2 places, we get 1300, or 13 * (10 ** 2). And if we take 12345 and "right-shift" by 3 places and then remove the decimal part, we get 12, or Math.floor(1234...

JavaScript • Bitwise Operators - Real World Examples (snippets)

Set different property to text in single UILabel

The first step you need to preform is to create a NSMutableAttributedString object. The reason we create a NSMutableAttributedString instead of NSAttributedString is because it enables us to append string to it. NSString *fullStr = @"Hello World!"; NSMutableAttributedString *attString =[...

iOS • attributedText in UILabel

Organizing new invoice numbers

Incrementing an invoice number and saving its value is a frequent task. Using CustomDocumentProperties (CDPs) is a good method to store such numbers in a relatively safe way within the same work book, but avoiding to show related cell values simply in an unprotected work sheet. Additional hint: A...

excel-vba • CustomDocumentProperties in practice

Docker and docker-compose

First of all, we will need to create our Dockerfile. A good example can be found on this blog by Nick Janetakis. This code contains the script that will be executed on our docker machine at the moment of start.For this reason, we are installing all the required libraries and ends with the start of ...

Ruby on Rails • Rails on docker

Carefully Closing a Scanner

it can happen that you use a scanner with the System.in as parameter for the constructor, then you need to be aware that closing the scanner will close the InputStream too giving as next that every try to read the input on that (Or any other scanner object) will throw an java.util.NoSuchElementExcep...

Java Language • Scanner

Delete local branches that have been deleted on the remote

To remote tracking between local and deleted remote branches use git fetch -p you can then use git branch -vv to see which branches are no longer being tracked. Branches that are no longer being tracked will be in the form below, containing 'gone' branch 12345e6 [origin/bran...

Git • Tidying up your local and remote repository

Convert blocking method to asynchonous

The following method will take a second or two depending on your connection to retrieve a web page and count the text length. Whatever thread calls it will block for that period of time. Also it rethrows an exception which is useful later on. public static long blockingGetWebPageLength(String urlS...

Java Language • CompletableFuture

Set different locale for md-datepicker

This example requires importing DateAdapter. import {DateAdapter} from '@angular/material'; datepicker.component.html: <md-input-container> <input mdInput [mdDatepicker]="picker" placeholder="Choose a date"> <button mdSuffix [mdDatepickerToggle]="pi...

angular-material2 • md-datepicker