
About me:
My sig (similar in spirit to Fun With Reserved Keywords):Here is a related hello world:perl le 'exp tr qw s my not vec eq abs do le chop q ge print lc if sort s qq socket y qx cmp s q qq or rand chop'
sort cos or s qq q and s m m print chr ord for qw q hex eval le lt oct q m and eval xor uc print lc qq m m and eval qq x not sin print chr ord for qw q warn open ref le do qx xor sleep log print qq q q if localtime sqrt chop
My bookmarks:
I tend to bookmark nodes related to theoretical topics like applied discrete math, algorithms, computability & complexity. Sorting a list of IP addresses (aka Why I hate Big O)
 (OT?) Usefulness of CS
 Perl regular expressions vs. RL, CFL, CSL (expressivity of Perl regexes)
 An informal introduction to O(N) notation (except that this reply is dead wrong)
 Re: similar texts !? (joint Kolmogorov complexity approximation)
 Re^2: Equivalency of Code (halting problem undecidability proof in 3 lines of perl)
 Re^2: Equivalency of Code (modern computers = finite state machines)
 Re^2: OT: Finding Factor Closest To Square Root (NPcomplete subset sum in disguise)
 Re: Empirically solving complex problems ("NPcomplete" ≠ "don't bother")
 Re^3: Representing all data as Lists (algorithmic analysis & assumptions)
 Distribute MP3 recordings optimally to CDRs (NPcomplete binpacking in disguise)
 Problematic post on teaching programming
 BigO Notation  What is it good for?
 Re: An informal introduction to O(N) notation (n/2 ≠ log(n))
 Re: Regexp generating strings? (decision properties of regular languages are decidable)
 Re: back translating regular expressions (halting problem ≠ infinite loop)
 Re^2: perl not omnipotent? let's see! (halting problem ≠ ChurchTuring thesis)
 Partitions of integers & sets
 Restricted integer partitions (i.e, making change for an amount)
 Combinations (subsets of a fixed size)
 Power set (all subsets)
 Permutations (works for multisets, too)
 Derangements (permutations with no fixed points)
 See also Re^3: Random Derangement Of An Array for how to uniformly sample derangements
 Understanding & Using Iterators (writing encapsulated iterators; offsite)
 Recursivelygenerated Iterators (converting recursions into callbackbased iterators).
 NestedLoops and the Odometer Model (callbackbased iterators with NestedLoops)
 Re: Question about recursively generated iterators (another generalpurpose iterator transformation)
 Combinatorial Object Server (offsite)
 DBI recipes
 Re: similar texts !? (approximation of mutual information, using compression)
 Re: recursive anonymous subroutines (Y combinator)
 Aristotle's use.perl journal entry on Y combinators
 Operator Associativity and Eliminating LeftRecursion in Parse::RecDescent
 My new favorite sorting algorithm (offsite, not safe for the humordeficient)
 Perl Format String Vulnerabilities  good overview of s/printf security issues (offsite)
My contributions:
Here are some of my highestranked nodes: Fun With Reserved Keywords
 Mandelbrot flythrough
 Pure regex Hamiltonian Circuit solution
 A Beginning Guide To Evolutionary Algorithms
 Golf: Buying with exact change
 The greedy changemaking problem using regexes
 Announcing "Other Users" stats (Are you addicted to PM?)
 Re: Weighted random numbers generator
 Re: Round robin tournament problem
 See also solutions to Perl QOTW
 HTML::Template macros
 Breadthfirst method dispatch
 Re: Problem assigning values to Hash (see very bottom 2 lines)
 Iterating over combinations
 Re: Generator of integer partitionts of n
 argmin & argmax
 Re^3: Regexes: finding ALL matches (including overlap)
 Re^3: Delimited Backtracking with Regex (with captures)
 Re: Sampling from Combination Space (ranking & unranking combinations)
 Re: find all paths of length n in a graph
 Re^2: Using overload to parse arithmetic terms (representing arithmetic expressions for prettyprinting)
 Partitioning a set into parts of given sizes
 Re: Challenge: Egg Timer Puzzles (code for calculating GCD with Bezout coefficients; i.e, the extended Euclidean algorithm)
 Memoryless iterator for integer partitions
 Re: challanging the dictionary (NPcomplete problem in disguise)
 Re: Bitwise File Shredding (secretsharing and information theory)
 Re: (contest) Help analyze PM reputation statistics (information theory)
 Re: Are Perl patterns universal? (universality of computational models)
 Re: Comparative satisfiability of regexps. (decision problems of regular languages)
 Re: Create hierarchies from list of keywords  well known algorithm? (decision tree learning)
 Re: Random Math Question (pseudorandom generation)
 Re: Algorithm to fit photos into spaces on pages (recasting a problem in terms of regular languages)
 Re: OT(ish)  Best Search Algorithm (an application of biconnectivity in graphs)
Evolutionary algorithms links:
In a previous life, I was very interested in evolutionary algorithms. Here are some (biased) links, which are by now terribly outofdate:Perl Modules:
 Algorithm::Evolve, by me! Flexible enough for lots of experimenting, but not comprehensive.
 Algorithm::Evolutionary probably most complete (and complex).
 AI::Genetic also looks like a good choice, though I haven't looked at it throroughly.
 Algorithm::Genetic, no crossover operators.
 AI::GA, little control over selection/replacement. String chromosomes only.
 A Beginning Guide To Evolutionary Algorithms by yours truly.
 Genetic algorithms applied with Perl, from IBM's "Cultured Perl" column
 Evolutionary computation in Perl and some YAPC presentation slides from the author of Algorithm::Evolutionary
 Online lecture notes: Optimization & Modelling With Artificial Life, by Dan Ashlock (my old professor)
 Genetic Programming or breeding Perls. I also wrote a reimplementation of this idea using my Algorithm::Evolve module. It's included in the distribution's examples.
 Looking for help with AI::Genetic and classroom scheduling
Random:
What famous people had to say about me: "The vanity of teaching doth oft tempt a man to forget he is a blockhead."
 George Savile, first Marquis of Halifax, 16331695  "The great person is ahead of their time, the smart make something out of it, and the blockhead, sets themselves against it."
 Jean Baudrillard  "A learned blockhead is a greater blockhead than an ignorant one."
 Benjamin Franklin  "No man but a blockhead ever wrote except for money."
 Samuel Johnson  The bookful blockhead, ignorantly read
With loads of learned lumber in his head.
 Alexander Pope  "The liar at any rate recognizes that recreation, not instruction, is the aim of conversation, and is a far more civilised being than the blockhead who loudly expresses his disbelief in a story which is told simply for the amusement of the company."
 Oscar Wilde  "A grave blockhead should always go about with a lively one  they show one another off to the best advantage."
 William Hazlitt  "A blockhead cannot come in, nor go away, nor sit, nor rise, nor stand, like a man of sense."
 Jean de la Bruyere  "There never was any party, faction, sect, or cabal whatsoever, in which the most ignorant were not the most violent; for a bee is not a busier animal than a blockhead."
 Alexander Pope  "Being a blockhead is sometimes the best security against being cheated by a man of wit."
 François, Duc De La Rochefoucauld  "When there is sympathy, there needs but one wise man in a company and all are wise,—so, a blockhead makes a blockhead of his companion. Wonderful power to benumb possesses this brother."
 Ralph Waldo Emerson
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