## Classifying Iris dataset using Naive Bayes Classifier

The Iris Dataset is a multivariate dataset. It has 5 attributes, the first one is sepal length (Numeric), second is sepal width (Numeric) third one is petal length (Numeric), the fourth one is petal width (Numeric) and the last one is the class itself. We have 150 rows that are equivalent to 150 flowers collected those flowers are divided into the different category. They are similar flowers that are Iris but the different category like Iris-setosa, Iris-versicolor, and Iris-virginica. It is important to know about these patterns because in future if you see similar data we can say that this data belong to the certain pattern. Based on these data, we can predict which kind of the Iris flower does new flower belongs. It is supervised data since we have the class (Nominal).

Data visualization:  As we can see there are three classes. Blue (Iris-setosa), Red (Iris-versicolor), and Sky Blue (Iris-virginica). There are equivalently distributed so during the analysis we don’t have to normalize it. There is same frequency of data of all class. Now let us analyze petal length graph. We can distinctly analyze that if the petal length is from 1 to 2 then it is of Iris-setosa. Similarly, we can analyze others using attributes graph.

Basically, the task is to assign a new data to one or more classes or categories is classification or categorization. Naive Bayes is a simple technique for constructing classifiers: models that assign class labels to problem instances, represented as vectors of feature values, where the class labels are drawn from some finite set. It assumes that the value of a particular feature is independent of the value of any other feature, given the class variable. For example, a fruit may be considered to be an apple if it is red, round, and about 10 cm in diameter. A naive Bayes classifier considers each of these features to contribute independently to the probability that this fruit is an apple, regardless of any possible correlations between the color, roundness and diameter features.

Python Code: Using Python weka wrapper for NaiveBayesUpdateable
Result

=== Summary ===
Correctly Classified Instances         144               96      %
Incorrectly Classified Instances         6                4      %
Kappa statistic                                             0.94
Mean absolute error                                     0.0324
Root mean squared error                            0.1495
Relative absolute error                                 7.2883 %
Root relative squared error                          31.7089 %
Total Number of Instances                            150

=== Confusion Matrix ===
a                  b                    c                       <-- classified as
50                0                    0                     |  a = Iris-setosa
0                  48                 2                     |  b = Iris-versicolor
0                 4                     46                  |  c = Iris-virginica

From this Confusion Matrix, we found that 50 of data is Iris-setosa from the above chart. Then it was able to classify 48 separate ways with 2 errors for Iris-versicolor. For Iris-virginica, 46 were rightly classified and 4 of them were an error.

The naive bayes model is comprised of a summary of the data in the training dataset. This summary is then used when making predictions. The summary of the training data collected involves the mean and the standard deviation for each attribute, by class value. For example, if there are two class values and 7 numerical attributes, then we need a mean and standard deviation for each attribute (7) and class value (2) combination that is 14 attribute summaries. These are required when making predictions to calculate the probability of specific attribute values belonging to each class value. We can break the preparation of this summary data down into the following sub-tasks:
1.       Separate Data By Class
2.       Calculate Mean
3.       Calculate Standard Deviation
4.       Summarize Dataset
5.       Summarize Attributes By Class

We are now ready to make predictions using the summaries prepared from our training data. Making predictions involves calculating the probability that a given data instance belongs to each class, then selecting the class with the largest probability of the prediction. We can divide this part into the following tasks:
1.       Calculate Gaussian Probability Density Function
2.       Calculate Class Probabilities
3.       Make a Prediction
4.       Estimate Accuracy

References
https://github.com/fracpete/python-weka-wrapper

## Trouble Installing python-pip in Ubuntu

Recently I was facing problem installing the pip in my ubuntu 16.04. After some research I found a solution which is as follow:
python-pip is in the universe repositories, therefore use the steps below:
Try this steps one by one
sudo apt-get install software-properties-common
sudo apt-get update
sudo apt-get install python-pip

## Simple Guess Number using Servlet

______________________________________________________________________________

HelloServlet.java
______________________________________________________________________________

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

/**
* Created by yubraj on 11/6/16.
*/
@WebServlet(urlPatterns = {"/HelloServlet"})
public class HelloServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<body>");
out.println("Hello World");
out.println("</body>");
out.println("</html>");
out.flush();
out.close();
}
}

________________________________________________________________________________

LogonServlet.java
______________________________________________________________________________

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

/**
* Created by yubraj on 11/6/16.
*/
@WebServlet(name = "LogonServlet", urlPatterns = {"/LogonServlet"})
public class LogonServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<body>");
out.print("Welcome user");
}else {
out.println("<form method=POST action=LogonServlet>");
out.println("<input type=submit value='Logon'>");
out.println("</form>");
}
out.println("</body>");
out.println("</html>");
out.close();

}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<body>");
out.println("<form method=POST action=LogonServlet>");
out.println("<input type=submit value='Logon'>");
out.println("</form>");
out.println("</body>");
out.println("</html>");
out.close();
}
}

______________________________________________________________________________

guessNumber.java
______________________________________________________________________________

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;

/**
* Created by yubraj on 11/6/16.
*/
@WebServlet(name = "guessnumber", urlPatterns = {"/guessnumber"})
public class guessnumber extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
HttpSession session = request.getSession(true);
PrintWriter out = response.getWriter();
int num = Integer.parseInt(request.getParameter("number"));
int randNumber = Integer.parseInt(session.getAttribute("randNum").toString());

out.println("<html>" +
"<title>Guess Number Game</title>" +
"<body>");
if(num == randNumber){
out.println("Congratulation you won");
out.println("<br><a href='/guessnumber'>Try Again</a>");
}else if(num>randNumber){
out.println("Number is too high. Try Again!");
out.println("<br><a href='/guessnumber'>Try Again</a>");
}else{
out.println("Number is too low. Try Again!");
out.println("<br><a href='/guessnumber'>Try Again</a>");
}
out.println("</body></html>");

}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
Random rand = new Random();
int x = rand.nextInt(10);

HttpSession session = request.getSession(true);
session.setAttribute("randNum", x);

PrintWriter out = response.getWriter();
out.println("<html>" +
"<title>Guess Number Game</title>" +
"<body>" +
"Enter the number between 1 and 10"+
"<form method=POST action=guessnumber>" +
"<input type=number name=number />" +
"<input type=SUBMIT value=Enter />" +
"</form>"+
"</body></html>");
System.out.println(x);
}
}

------------------------------------------------------------------------------------------------------------
Web.xml
------------------------------------------------------------------------------------------------------------

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1">
<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>HelloServlet</servlet-class>
</servlet>
</web-app>

## Simple Guess Number Game using JSP

<%@ page import="java.util.ArrayList" %>
<%--
Created by IntelliJ IDEA.
User: yubraj
Date: 11/20/16
Time: 4:27 PM
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<title>Number Guess System</title>
<style>
.error{ color: red; }
.success { color: greenyellow; }
</style>
<body>
<h1>Hello world</h1>
<%
for(int i = 1; i<=10; i++){ %>
<h5><%= +i%></h5>
<% } %>
<h1>Number Guess System</h1>
<p>Guess Number within 1 and 10</p>

<%
final HttpSession       Sess = request.getSession();
final boolean           JustStarted = Sess.isNew();
final Integer           randomNumber;

if(JustStarted){
randomNumber = new Integer(new java.util.Random().nextInt(10));
System.out.println("Random Number : " + randomNumber);
Sess.setAttribute("number", randomNumber);
} else {
randomNumber = (Integer) Sess.getAttribute("number");
}
%>

<%
String inputText = request.getParameter("number");
String errorMsg = null;
boolean success = false;

if(!JustStarted) {
if (inputText != null && inputText.length() > 0) {
int myNumber = Integer.parseInt(inputText);
if (randomNumber != myNumber) {
if (myNumber > randomNumber)
errorMsg = "Number too large!";
else
errorMsg = "Number too Low!";
} else {
errorMsg = "Congrats! you win";
success = true;
}
}
}
%>

<div>
<% if(errorMsg != null){ %>
<p class="<% if(success){ %>
success
<% }else{ %>
error
<% } %>
">
<%= errorMsg %>
</p>
<% } %>
<form method="post">
<label for="number">Enter the Number : </label> <input type="tex" name="number" id="number" maxlength="3">
<input type="submit" value="Submit">
</form>
</div>
</body>
</html>

## Angular 2 - Part 6 [ Understanding AppModule ]

In our angular-cli generated app we have one module called app.module.ts inside the app dir. So whats the use of this, as in the previous post we said that this is used to bootstrap the component but lets examine this line by line what all other stuffs it can do
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';

import { AppComponent } from './app.component';

@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
FormsModule,
HttpModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }

1. At first we are importing all the modules that are used in our app
1. BrowserModule :  registers critical application service providers. It also includes common directives like NgIf and NgFor which become immediately visible and usable in any of this modules component templates.
2. NgModule: This module is used to import angular core Module lib
3. FormsModule: This module is used to handle the input related tasks
4. HttpModule: This mdule is used to make http services available in our module
2. @NgModule : It is imported from angular/core. Here we tell angular what is used in our app.
1. declaration: What directives we have used in our app, Components are directives. It basically tells which componets should I use through out my application.
2. imports: which other modules should I use. like browser module is used to use other default directives.
3. providers: is used if we want to have application wise services
4. bootstrap:  it is used to bootstrap the components that is used in this module
3. The export keyword enable out module to be used externally
Thats all for now. In the next session we will talk about the templates \m/

## Angular 2 - Part 5 [ How Angular App get started ]

How Angular 2 App get started?
Angular 2 is a single page app and will contains only one file called index.html in the root folder. although this html file doennot even contains any js files then how the fuck it get started:

Index file
<!doctype html>
<html>
<meta charset="utf-8">
<title>FirstApp</title>
<base href="/">

<meta name="viewport" content="width=device-width, initial-scale=1">
<body>
</body>
</html>

Well when we compile and run the app then the angular-cli will dynamically add the required js files in the page. Which we can see the source in the page while its running

Well then where the fuck is our code?
The answer is it all we be inside the main.bundle.js file

here is the flow
1. At first the angular app will always use main.ts file which will bootstrap the our app and create a js file at the run time. Inside teh main.ts file we have

platformBrowserDynamic().bootstrapModule(AppModule);

Which will load the AppModule from the module inside the app directory after importing it using

import { AppModule } from './app/';
2. Then the app will use the app.module.ts inside the app dir which will again bootstrap the AppComponent which we have created earlier in this series.

bootstrap: [AppComponent]
3. The Main this about angular 2 is that it will not load all the component at the beginning. It will only load the component which is in the index.html file which is app-root in our case. Its a lazy loading which will increase the performance.
4. So the main flow is
main.ts -> load the main module used in the index.html -> the main module will bootstrap the Component -> then main.ts will bootstrap the app and create a single main.bundle.js and add it to the main page -> then we enjoy :)

Happy Coding geeks. In the next session we will talk about the AppModules \,,/

## Angular 2 - Part 4 [ Understanding the Component ]

As we have seen angular is composed of lots of modules and component but what really is a component. Well we will learn this in this post

What our normal  app structure looks like - Here I am using the angular-cli

Here we have app.component.ts file inside the app directory which contains following beautiful lines of code:

import { Component } from '@angular/core';

@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent {
title = 'app works!';
}

1. The class name for this component is AppComponent
2. The AppComponent is imported from core angular i.e. @angular/core
3. @Component is a decorator which makes this class something special, without this decorator this class will be nothing.
4. Inside @Component decorator we have
1. selector : The selector is what allow us to use our component. Its like creating our own html tag which contains certain user define properties. This selectors normally acts like a css selector.
1. Lets say we want to use selector as a ID or a class rather then creating this a new tag then we just need to modify selector as
selector: '.app-root ' for class or
selector: '#app-root' for id
So that for eg. whenever we call div with class app-root then the same above component get loaded inside the div and for the ID as well.
2. templateUrl : yeah! you are right every component must contains the html either inline type or may be load the different html page as shown in the given code. Here we are loading external html page in this component. If we are using the external html page then we need to use templateUrl otherwise we can write html also like

template : '<div class="myAwesomeClass">{{title}}</div>';
3. styleUrls: This is same as we decribed in the template section. we can define our own custom css for our componet either using the external css file or inline.
5. export this keyword enable our component to be exported and use by other component too.
1. here title is a property which will be used in our template using the {{}} which is as we can compare with the scope in the angularjs 1
Thats all coders follow next tutorial for more happy coding moments \,,/

## Anuglar 2 - Part 3 - Installing through Angular-Cli

we can now install the angular 2 cli in our system so that it can be used in the future with ease. It can also used to create the angular project with the simple commands in the terminal

for this we need to follow the following commands. Remember I am using the ubuntu terminal some commands can vary in windows and in mac it may need sudo permission :)

Step 1
Install Angular-cli globally by using npm install -g angular-cli

Step 2
Make new directory using the command mkdir or whatever other technique you want. For this I am using mkdir myAngApp

Step 3
create a angular app in the above created directory using ng new <name of your project>
like ng new first-app

Step 4
now go to the project directory by cd first-app and then serve the angular project using the ng serve.
Now you can view the project in browser using localhost:3000 or what ever port your system has assigned please view the terminal for the port info.

WOW you have done it Congrats please tune for the next part for more happy coding :)

## Angular 2 - Hello Angular's new world

Before starting this part please make sure that you have installed node in yout system.
For this complete series I am using node v6.2.2 in the ubuntu 16.04 LTS system.

Step 1: Create your app directory
goto terminal or cmd and type mkdir myapp

Step 2: Open any text editor and create below files and save them in the respective dir i.e. myapp dir

Package.json : [The package.json will contain the packages that our apps require. These packages are installed and maintained with npm (Node Package Manager).]

{
"name": "angular-quickstart",
"version": "1.0.0",
"scripts": {
"start": "tsc && concurrently \"tsc -w\" \"lite-server\" ",
"lite": "lite-server",
"postinstall": "typings install",
"tsc": "tsc",
"tsc:w": "tsc -w",
"typings": "typings"
},
{
"type": "MIT",
}
],
"dependencies": {
"@angular/common": "~2.1.0",
"@angular/compiler": "~2.1.0",
"@angular/core": "~2.1.0",
"@angular/forms": "~2.1.0",
"@angular/http": "~2.1.0",
"@angular/platform-browser": "~2.1.0",
"@angular/platform-browser-dynamic": "~2.1.0",
"@angular/router": "~3.1.0",
"angular-in-memory-web-api": "~0.1.5",
"bootstrap": "^3.3.7",
"core-js": "^2.4.1",
"rxjs": "5.0.0-beta.12",
"systemjs": "0.19.39",
"zone.js": "^0.6.25"
},
"devDependencies": {
"concurrently": "^3.0.0",
"lite-server": "^2.2.2",
"typescript": "^2.0.3",
"typings":"^1.4.0"
}
}

tsconfig.json

{
"compilerOptions": {
"target": "es5",
"module": "commonjs",
"moduleResolution": "node",
"sourceMap": true,
"experimentalDecorators": true,
"noImplicitAny": false
}
}

typings.json

{
"globalDependencies": {
"core-js": "registry:dt/core-js#0.0.0+20160725163759",
"jasmine": "registry:dt/jasmine#2.2.0+20160621224255",
"node": "registry:dt/node#6.0.0+20160909174046"
}
}

Note:: A large number of libraries of the JavaScript extends JavaScript environment with features and syntax which is not natively recognized by the TypeScript compiler. Thetypings.json file is used to identify TypeScript definition files in your Angular application.
In the above code, there are three typing files as shown below:
1. core-js: It brings ES2015/ES6 capabilities to our ES5 browsers.
2. jasmine: It is the typing for Jasmine test framework.
3. node: It is used for the code that references objects in the nodejs environment.

systemjs.config.js

(function (global) {
System.config({
paths: {
// paths serve as alias
'npm:': 'node_modules/'
},
// map tells the System loader where to look for things
map: {
// our app is within the app folder
app: 'app',
// angular bundles
'@angular/core': 'npm:@angular/core/bundles/core.umd.js',
'@angular/common': 'npm:@angular/common/bundles/common.umd.js',
'@angular/compiler': 'npm:@angular/compiler/bundles/compiler.umd.js',
'@angular/platform-browser': 'npm:@angular/platform-browser/bundles/platform-browser.umd.js',
'@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
'@angular/http': 'npm:@angular/http/bundles/http.umd.js',
'@angular/router': 'npm:@angular/router/bundles/router.umd.js',
'@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js',
// other libraries
'rxjs':                      'npm:rxjs',
'angular-in-memory-web-api': 'npm:angular-in-memory-web-api',
},
// packages tells the System loader how to load when no filename and/or no extension
packages: {
app: {
main: './main.js',
defaultExtension: 'js'
},
rxjs: {
defaultExtension: 'js'
},
'angular-in-memory-web-api': {
main: './index.js',
defaultExtension: 'js'
}
}
});
})(this);

Step 3: To install packages
npm install

Step 4: Create new dir called app
mkdir app and create

1. app.component.ts

import { Component } from '@angular/core';
@Component({
selector: 'my-app',
template: '<h1>My First Angular App</h1>'
})
export class AppComponent {
}

NOTE::
The above code will import the Component and View package from angular2/core.
1. The @Component is an Angular 2 decorator that allows you to associate metadata with the component class.
2. The my-app can be used as HTML tag to injecting and can be used as a component.
3. The export specifies that, this component will be available outside the file.

2. app.module.ts
import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

import { AppComponent }   from './app.component';
import { ContactComponent }   from './dataBind/dataBind.component';

@NgModule({
imports:      [ BrowserModule ],
declarations: [ AppComponent ],
bootstrap:    [ AppComponent]
})

export class AppModule { }

3. main.ts
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app.module';
const platform = platformBrowserDynamic();
platform.bootstrapModule(AppModule);

NOTE::
1. The main.ts file tells Angular to load the component.
2. To launch the application, we need to import both Angular's browser bootstrap function and root component of the application.

STEP 5:: Create index.html in the roor dir
<html>
<title>Angular QuickStart</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Polyfill(s) for older browsers -->
<script src="node_modules/core-js/client/shim.min.js"></script>
<script src="node_modules/zone.js/dist/zone.js"></script>
<script src="node_modules/systemjs/dist/system.src.js"></script>
<!-- 2. Configure SystemJS -->
<script src="systemjs.config.js"></script>
<script>
System.import('app').catch(function(err){ console.error(err); });
</script>
<!-- 3. Display the application -->
<body>
<data-bind></data-bind>
</body>
</html>

STEP 6: Now Run
using the terminal command npm start

Now the page will be opened in the browser with the text "My first Angular App" text

## Angular 2 - Introduction

What is Angular 2?
Angular 2 is an open source JavaScript framework to build web applications in HTML and JavaScript and has been conceived as a mobile first approach.

History
The beta version of Angular 2 has been released in the March of 2014.

Why to use Angular 2?
Angular 2 is simpler than Angular 1 and its fewer concepts make it easier to understand. You can update the large data sets with minimal memory overhead.It will speed up the initial load through server side rendering.

Features
1. Angular 2 is faster and easier than Angular 1.
2. It supports latest the version of browsers and also supports old browsers including IE9+ and Android 4.1+.
3. It is a cross platform framework.
4. Angular 2 is mainly focused on mobile apps.
5. Code structure is very simplified than the previous version of Angular.
6. Angular 2 has a more powerful templating system then Angular 1.
8. Angular 2 is much more testable then Angular 1.

1. If an application is a heavy load, then Angular 2 keeps it fully UI responsive.
2. It uses server side rendering for fast views on mobile.
3. It works well with ECMAScript and other languages that compile to JavaScript.
4. It uses dependency injection to maintain applications without writing too long code.
5. Everything will be the component based approach.

Angular 2 is mainly rewritten to eliminate the issues we were facing in Angular 1 version consider its performance issue or maintainability in large scale.

## Millennium Prize Problems: Solve 1 Problem get US 1 million dollar

Are you want to  won 1 million dollar  prize from the solve mathematics problem, Here is the some Millennium Prize Problems are seven problems in mathematics. These are the problems:

1. Birch and Swinnerton-Dyer conjecture,  (Unsolved)
2. Hodge conjecture,  (Unsolved)
3. Navier–Stokes existence and smoothness,  (Unsolved)
4. P versus NP problem,  (Unsolved)
6. Riemann hypothesis, and  (Unsolved)
7. Yang–Mills existence and mass gap.  (Unsolved)

If you solve any of the above problem, you will won US \$1 million prize being awarded by the institute to the discoverers.At present, the only Millennium Prize problem to have been solved is the PoincarÃ© conjecture, which was solved by the Russian mathematician Grigori Perelman in 2003.

## R Programming: 1. Introduction and installation

This this first tutorials about the R programming, we going to post all the tutorials about the R programming too.

R programming is used to gives the statistically data  modeling with textual and  graphically representation as a output with nice format. R provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering, …) and graphical techniques, and is highly extensible.

Here is the first step of start of R programming to to understand the basic syntax in R. You can practice more and more from the http://tryr.codeschool.com/ .

Installation(Window):

Click on the official R programming site (http://www.r-project.org). Search for the Download section

Click “download R” to get the proper mirror. This should take you to a page something like bellow.

Choose the link for Iowa State University or any other mirror you like.

Choose your operating system. In the tutorial case it was selected Microsoft Windows.

Click “install R for the first time”.

Click on “Save file” to save the installer to your computer.

Double click the .exe file for installation.

Click “Run” to start the installation. Follow the steps. Click next, accept agreement, select your installation folder and finish the installation.

Working on R

Select the R application from your start menu. All coding style should be same what you practiced on R code school.

1. Get and set working directory

getwd()
setwd("/path/to/your/working/directory")

1. ## List of commands

Here are some commands that you can use in your R script.

 Command/word Description Example # The characters after are considered comment #this is a comment cat Print a message to the console (like System.out.println in Java) cat("Hello World!\n") source Execute a R script file previously created source("myScript.r") <- Assign a value to a variable one <- 1 Hello <- "Hello" install.packages Download and install a package install.packages("rpart") library Load a installed library to your R script load(rpart)

OBS: R is case sensitive, so Variable is different from variable.

Thank you !!!