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LED Blinking on Arduino : Learn Arduino


LED Blinking on Arduino Uno should be your first Arduino project. Arduino Uno has an on-board or built-in LED, in this project we will see how to blink it. Parts you will need: An Arduino Uno Steps: Connect Arduino with your computer. Download, install and open Arduino IDE. [hide_from_apps container=”span”](See how)[/hide_from_apps] Within IDE chooose File Menu > Examples > 01...

An Introduction to Arduino Platform : Learn Arduino


Arduino is an open-source hardware prototyping platform. It is widely used today in electronics projects because it is easy to learn, simple in design, well documented and cheaper. We call it platform because it is both hardware circuit as well as piece of software, the IDE. It also has its own programming language. All these open-source components collectively makes the Arduino platform. Bit of...

Reclaiming Your Privacy on Android


A major threat to your privacy emanates from your smart phone. These devices have become central medium of social interaction for everyone. Android is the only open source platform among the popular smart phone operating systems. But even with Android your privacy is under attack as large corporations have figured out that data is the new oil. Android privacy threats, for the scope of this...

Merge Sort : Why Sorting Lists in Halves is Interesting?


Searching and sorting are two basic problems which occur in various more complex computing problems. Time complexity of sorting algorithms cannot get better than O (nlogn). Many popular algorithms have polynomial time complexity O (n2). Undoubtedly sorted lists are interesting because we can solve many problems using it: from binary search to Kruskal’s algorithm. This post tries to point...

Zeno’s Paradoxes


Zeno was a Greek philosopher who lived circa 490 to 430 BC. Zeno’s paradoxes paradoxes have puzzled us for more than 2500 years now; three of them are presented here for you to ponder upon. 1. Achilles and the tortoise In a race, the quickest runner can never overtake the slowest, since the pursuer must first reach the point whence the pursued started, so that the slower must always hold a...

How Credit Card Numbers Work?


How credit card numbers work? It is interesting to see how quickly payment gateway web page can check whether given card number is valid. There is a pattern that every card number adheres to. Such patterns can be matched using JavaScript. A credit card number is made-up of four different components: MII (digit 1), IIN (digits 1-6), IAI (digits 7-15) and a check digit (last digit). Let’s see...

Apache Log Visualization with Matplotlib : Learn Data Science


This post discusses Apache log visualization with Matplotlib library. First, download the data file used in this example [hide_from_apps container=”span”]from here.[/hide_from_apps][show_only_in_apps]from here.[/show_only_in_apps] We will require numpy and matplotlib In [1]: import numpy as np import matplotlib.pyplot as plt numpy.loadtext() can directly load a text file in an...

NLTK Example : Detecting Geographic Setting of Sherlock Holmes Stories


As a young adult nothing thrilled me more than Jeremy Brett’s performance as Sherlock Holmes. “You know my methods, apply them!” he would say. So let’s try to play Sherlock ourselves. We use Natural Language Tool Kit or NLTK to guess setting of a Sherlock story in terms of its geographic location. In this NLTK example, our approach is very naive: identify the most frequent...

Building a Movie Recommendation Service with Apache Spark


In this tutorial I’ll show you building a movie recommendation service with Apache Spark. Two users are alike if they rated a product similarly. For example, if Alice rated a book 3/5 and Bob also rated the same book 3.3/5 they are very much alike. Now if Bob buys another book and rates it 4/5 we should suggest that book to Alice, that’s what a recommender system does. See references...

GraphFrames PySpark Example : Learn Data Science


In this post, GraphFrames PySpark example is discussed with shortest path problem. GraphFrames is a Spark package that allows DataFrame-based graphs in Saprk. Spark version 1.6.2 is considered for all examples. Including the package with PySaprk shell : pyspark --packages graphframes:graphframes:0.1.0-spark1.6 Code: from pyspark import SparkContext from pyspark.sql import SQLContext sc =...

Devji Chhanga

I teach computer science at university of Kutch since 2011, Kutch is the western most district of India. At iDevji, I share tech stories that excite me. You will love reading the blog if you too believe in the disruptive power of technology. Some stories are purely technical while others can involve empathetical approach to problem solving using technology.

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