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arnabdotorg

Re:Automating Card Games Using OpenCV and Python on Sunday June 16, 2013 @06:46PM (#5890375)
Haha, sure. Since this was a random fun project, the code was written with the objective function being "least amount of code to get the job done well enough" :)
Re:Automating Card Games Using OpenCV and Python on Sunday June 16, 2013 @06:38PM (#5890343)
Hi guys, author of the blog post here. I put up the code from the blog post at

https://github.com/arnabdotorg/Playing-Card-Recognition

if anyone wants to play with it.

Re:Civic hackers seek to find their feet in India on Monday January 03, 2011 @05:32AM (#2062758)
Re:Ask HN: Storing spatial data in SQL on Wednesday November 17, 2010 @10:58PM (#1916793)
Postgres: http://www.postgresql.org/docs/8.1/static/indexes-types.html:

"PostgreSQL provides several index types: B-tree, R-tree, Hash, and GiST. R-tree indexes are suited for queries on two-dimensional spatial data."

PostGIS: http://postgis.refractions.net/ :

"PostGIS adds support for geographic objects to the PostgreSQL object-relational database. In effect, PostGIS "spatially enables" the PostgreSQL server, allowing it to be used as a backend spatial database for geographic information systems (GIS)"

Also see "Programming the K-means Clustering Algorithm in SQL": http://pdf.cx/6gc9a

Re:Building a Better Collage on Wednesday November 17, 2010 @08:26PM (#1916458)
Awesome stuff!
The key value is not as much in the data itself, as much as the _timeliness_ of the data. Access to the halfhose allows you to answer a _very_ valuable question:

"What's happening right now?"

This question is worth a lot of money, and something that doesn't have a good algorithmic solution(e.g. Google News.) Twitter is probably the only company that has a privacy-compliant solution to this, hence making it a very monetizable product.

Re:Fixing Facebook's Font Size Frustration on Friday November 05, 2010 @12:58AM (#1872103)
Well, it was a problem for me, so I fixed it, and thought I'd share :)

Notably my 2 issues were:

1) My eyes hurt so much that I preferred using my iPhone over a 24" screen. After installing this, my eyes are feeling much better. Maybe I'm just old.

2) Before, my Friends' status messages were 13px, everything else was 11px. I prefer that my friends' thoughts be more important than UI chrome.

Re:Ask HN: Do you use programming tricks in real life too? on Wednesday September 15, 2010 @07:06PM (#1696190)
Yes, I do. For example, I use all the tips mentioned on this page:

http://news.ycombinator.com/item?id=1695794

Re:Autocomplete your life with Greplin (YC W10) on Tuesday August 31, 2010 @04:30PM (#1650780)
Where's the autocomplete? I only see find-as-you-type -- there are no Google-suggest like suggestions, per se.

Also, I am very curious to see back-of-the-envelope calculations on resource usage -- e.g. what is the expected billing per user (in dollars)? ("Doesn't matter" is an acceptable answer for now, but I'm worried that this type of service is unreasonably expensive to provide and cannot be offset by ads/freemium models)

Re:Ask HN: Holy Crap I need an Idea on Monday August 16, 2010 @01:54PM (#1608552)
Taking this a step further:

1. Use Facebook Connect to create a library of things that you own. e.g. DVDs, tools.

2. Suggest Collections/activities that arise out of your social network: "Amy, Jon and you have all the Star Wars movies among you: Time for a Star Wars Marathon? David and Emma would be interested in joining(based on interests)!", or "Joanna and you have all the things needed to go camping".

3. Profit model: Suggest things to buy on Amazon that "completes" the collection: e.g. "If one of the three of you bought "Snatch", then you would have all the movies by Guy Ritchie"

This requires data mining for list generation (see Google Sets), Facebook APIs / Opengraph, location apis, and Amazon APIs, and has a money side to it.

[i hereby release this idea under the "buy me a beer if you use it" license]

Re:Ask HN: Sorting massive text files? on Saturday August 14, 2010 @02:14PM (#1603733)
Merge sort works very well if you have multiple cores available. The general idea is to split the file, sort in parallel, and then merge.

Here's a blog post I wrote about it:

http://arnab.org/blog/quick-and-easy-multicore-sort

Re:Ask HN: Open Source apps with lots of database tables? on Friday November 13, 2009 @03:54PM (#940793)
+1 on Drupal. It also implements sequences, etc.