Monthly Archives: August 2014

Hungarian Algorithm (Part II)

Posted on August 25, 2014 by Naren Sundar

View source file on Github [part 1 is not necessary to follow this] When I first looked up the Hungarian algorithm on Wikipedia, I was immediately drawn away from what seemed like a tortured graphical explanation and went straight to … Continue reading →

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Performance: Looping

Posted on August 23, 2014 by Naren Sundar

View source file on Github Before I finish off the Hungarian algorithm, I want to settle (nominally) the matter of performance with respect to array/vector based number-crunching in Haskell. I never sat down to consider this matter systematically and now … Continue reading →

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Young Tableau: Row-insertion (Part II)

Posted on August 18, 2014 by Naren Sundar

View literate file on Github > import Control.Lens > import Control.Monad > import Control.Monad.State > import Data.List > import Test.QuickCheck Having defined a Young Tableau, let’s consider one of the ways to construct it. How can you go about adding … Continue reading →

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Hungarian Algorithm (Part I): Minimal covering of zeros

Posted on August 17, 2014 by Naren Sundar

View source file on Github > module Main where > import Control.Lens hiding (assign) > import Control.Monad > import Data.List > import Data.Ord (comparing) > import Test.QuickCheck hiding (sample) > import qualified Data.IntSet as I I will resist posts on … Continue reading →

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Choices: Command Line Parsers

Posted on August 9, 2014 by Naren Sundar

View literate file on Github Like everything in Haskell, parsing command line arguments comes with its own marketplace. > {-# LANGUAGE DeriveDataTypeable #-} > > module Main where > import Prelude hiding (lines) > import Options.Applicative > import System.Environment (getArgs) … Continue reading →

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Quickie: Generating the powerset

Posted on August 4, 2014 by Naren Sundar

View literate file on Github > import Control.Monad The traditional way to generate the powerset of a list of elements is the following > powerset :: [a] -> [[a]] > powerset (x:xs) = map (x:) (powerset xs) ++ powerset xs … Continue reading →

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Young Tableau: Introduction (Part I)

Posted on August 1, 2014 by Naren Sundar

View literate file on Github I have a book sitting on my shelf: Young Tableaux by William Fulton (ISBN 0 521 56724 6). I bought it after having the fantastic chance to see these beautiful and deep combinatorial structures in … Continue reading →

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