(divisors z) → (Listof Natural)
z : Integer
Returns a list of all positive divisors of the integer z. The divisors appear in ascending order.

Another reason why Racket rocks, because optimizing trial-division for large numbers.

It makes solving the Fermat Exponent problem easy:

Apparently, there was a period of time in Beethoven's transition from classical formalist to bombastic romanticist (possibly accompanied by severe hearing loss and disillusionment with Napoleon) when musicians said, (translated from 19th-century German), "What the heck, Beethoven! This isn't music! My kids could write this!"

Elsewhere:

• Dragon Con followup: Female heroes and femininity | Feministe
• Charles Blow on bisexuality, gender, and fluidity Sexual Attraction and Fluidity - The New York Times
• Worth thinking about: Crossdreamers: Felix Conrad Talks about Transgender Research, Crossdreaming and Beach Clubbing
• I'm about halfway through this article on nonduality: True Nonduality and the Neo-Advaita - You are not done yet!

Bridge hands problem in C++

Bridge Hands

The bridge hands problem on programming praxis in Common Lisp.

Ozymandias

One-swap sorting problem in common lisp.

One-swap sorting problem in common lisp.

Given an array of unique integers, determine if it is possible to sort the array by swapping two elements of the array. For instance, the array [1,2,6,4,5,3,7] can be sorted by swapping 3 and 6, but there is no way to sort the array [5,4,3,2,1] by swapping two of its elements. You may use O(n) time, where the array has n integers, and constant additional space.

Number Puzzle: Racket Solution

A Number Puzzle | Programming Praxis Racket Solution

Gas Station Problem in Racket

Racket solution to the gas station problem:

Ordered words Problem

My racket solution to the Ordered Words Problem on Programming Praxis:

EDIT: A C++ solution.

EDIT EDIT: A Common Lisp solution.

bi-geek-pan linkspam 14 July 2015: OitNB, language documentary, factor, macros, african science fiction

bi

• Why Won't "Orange Is The New Black" Acknowledge That Bisexuals Exist
• Why Do I Sound So Gay? - The Daily Beast
• Bisexual Banter — Morgan talks about what he found most confusing as...

geek

• Factor, a practical concatenative language
• Fear of Macros a nice introduction to macro programming in Racket.

fan

• Why Africa is the new home of science fiction | Books | The Guardian

Programming Puzzle: Phonebook Problem in Racket and C++

My weekend puzzle, solutions to the Partitioning The Telephone Book problem at Programming Praxis.

• Racket code (pastebin)
• C++ code (pastebin)

(I'm an amateur, especially with C++. Do not emulate.)

Two Programming Links

Two programming links:

NASA fixed a bug in New Horizons a week before it hurtles by Pluto. They're working with a nine-hour delay.

Grant Rettke discusses lisp, forth, and minimalist programming.

Artist: Google's Image Recognition Engine

Neural net hallucination caused by force-feeding Google's image recognition engine.

If we apply the algorithm iteratively on its own outputs and apply some zooming after each iteration, we get an endless stream of new impressions, exploring the set of things the network knows about. We can even start this process from a random-noise image, so that the result becomes purely the result of the neural network, as seen in the following images:

Inceptionism: Going Deeper into Neural Networks Alexander Mordvintsev, Christopher Olah, and Mike Tyka, @ Google Research

Combinations: The Science Fiction Epic

Gets really weird about 4:30.

The video is cited in this paper (PDF).

Leonardo Numbers

The Leonardo Numbers problem @ Programming Praxis

My solution in Common Lisp

Let Over Lambda "This is Lisp"

But this is lisp. We're very non-functional and very proud of it.

— Doug Hoyte Let Over Lambda

Racket and Identicons

Using Racket to generate identicons:

I’ve always liked identicons, which WordPress and GitHub have used to great effect. The premise is simple: take a user identifier such as an IP or email address and deterministically convert it into an image based on a simple algorithm. To that I end I started hacking on Identikon - a little Racket program that generates different types of identicons based on rules modules.

Disable emacs ido caching for bad directories on windows

I’ve been having a problem with ido screwing up on windows. Here is a fix.

;;disable ido caching on windows
(require 'ido)
(when (equal system-type 'windows-nt)
  (setq ido-max-dir-file-cache 0)
  (add-to-list 'ido-work-directory-list-ignore-regexps
           "Local Settings")
  (add-to-list 'ido-work-directory-list-ignore-regexps
           "Application Data"))

Pastebin link