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Randomized Probabilistic Bag of Objects Data-Structure using Map

"Probabilistic Bag data-structure" Recently I was working on a NLP problem, wherein I needed this (this data-structure is a pretty simple thing which is already being used in industry also, I am sure). So here few important features or requirements that I had : NOTE: Any randomized data-structure works well only when it uses random-number generators which generate uniformly distributed values over the range. A probabilistic, randomized bag of objects data-structure with - a) Each object having some weight, b) Selection from this structure should be random but should be influenced by their weights c) The weights are positive and multiple objects can have same weight (there is no upper bound on weights but a lower bound of 0). So I searched online and there were some real great responses - I am basically consolidating them - There are many ways you can build such structures  - 1)   Using Lists : There are 2 main approaches using list Storing unique objec...
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How to build/create Bird's Feeder at Home

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I always wanted to buy a bird-feeder to feed birds in backyard of my home. So did some searching and found out few really good videos about how to build a bird-feeder with cheap soda/water bottles and which types of birds like what type of seeds/food. So here is my try to put it in a proper order: At first, what to feed to birds? There are different types of bird-feeders for different types of birds and their food/seeds. Now build relatively simple bird-feeder from 2-little plastic soda/pepsi/coke bottles, For small birds:- One more type -  Or use a milk carton:- Finally, bird's do need clean water - so using plastic plate and bottle - we can make a cheap and easy home-made water-feeder for birds, see it how:- Another one, Additional Links:- http://birding.about.com/od/birdfeeders/a/Make-A-Plastic-Bottle-Bird-Feeder.htm http://www.bbc.co.uk/northernireland/radiofoyle/breat...
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Very useful website about tips and notes of many languages, API and applications

Recently I found out this cool website by  Russ Bateman  (seems to be a really great knowledge source, from the notes and articles on following his website) His official website -  http://www.russellbateman.com/ Following it his website where you can find so many articles/detailed notes about many languages, API and applications e.g. git, svn, eclipse, Java, MongoDB and so on. http://www.javahotchocolate.com He is also one of the finalists for  Eclipse Community Awards Winners . http://www.eclipse.org/org/press-release/20100322_awardswinners.php It is a really great website with lots of information. For example:- Useful Tips/information about 1) Eclipse:-  http://www.javahotchocolate.com/notes/eclipse.html 2) GitHub:- http://www.javahotchocolate.com/notes/github.html 3) Git:-   http://www.javahotchocolate.com/notes/git.html  and  http://www.javahotchocolate.com/notes/git-training.html
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Fibonacci numbers (good videos)

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This article is in continuation with my last article about amazing patterns in Fibonacci number series. Here are few really interesting videos.  1.  Fibonacci Mystery - Numberphile (I love watching NumberPhile videos on Youtube. So I will start with it first) 2.  The Golden Ratio & Fibonacci Numbers: Fact versus Fiction (A Stanford University's video lecture about Fibonacci and Golden Ratio) 3.  Arthur Benjamin: The magic of Fibonacci numbers (A TED talk about Fibonacci numbers and their important in teaching mathematics) 4.  Doodling in Math: Spirals, Fibonacci, and Being a Plant [1 of 3]    5.  Doodling in Math: Spirals, Fibonacci, and Being a Plant [2 of 3]   6.  Doodling in Math: Spirals, Fibonacci, and Being a Plant [3 of 3] There is also an association named Fibonacci Association   →  http://www.mscs.dal.ca/Fibonacci/index.html Isn't it amazing...  That's why I like maths. :)
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Pattern of sum of digits of fibonacci numbers - Part I

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I think Fibonacci is one of the most studied sequences in mathematics and which is named after  Leonardo Fibonacci .  The Fibonacci numbers , and in conjunction the  golden ratio , are a popular theme in culture (from Wikipedia ). It is used in many real-world applications like stock markets predictions (e.g. retracement, etc). I was also fascinated so I started looking at pattern formed by Fibonacci numbers and I found out few amazing things about it:- Java code for printing  →  Fibonacci Series (left/right/normal aligned)  →  FiboSeries.java Important  →   Why am I doing it?  1. for the love of numbers and maths, and  2. I wanted to find  (which I haven't found yet)  n-th Fibonacci number without going through all previous Fibonacci numbers,  or at least find out how many digits are there in any n-th Fibonacci number  or what is the sum of all digits of such n-th Fibonacci number. 1. Fibonacc...
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How to build a basic web-page-grabber in java

"Website Grabber is a utility that can be used to mirror, copy, synchronize, download, scrub or "steal" a web site." - from Epicware at  http://www.epicware.com/webgrabber.html ( Important Warning - Web Grabber should be built with a lot of caution as it might cause problem to server and if not controlled to the web, in scenarios like crawler crawling all the web, following all the links on the web, so that might be the reason to not having so many Web-Grabber Application on internet. Because people might use them for stealing the website designs or stylesheets or framework, etc.) My purpose of publishing this blog is to make people aware, to make them literate about how do they (Grabbers) work and how they can be built, but using them wisely is an individual responsibility. Last semester, we had a project to build a fully functional web-crawler just like Googlebot or  Yahoo! Slurp or msnbot or Bingbot, etc  (right, not that powerful). And I knew previous...
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