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@onlurking
onlurking / programming-as-theory-building.md
Created Jun 1, 2020
Programming as Theory Building - Peter Naur
View programming-as-theory-building.md

Programming as Theory Building

Peter Naur

Peter Naur's classic 1985 essay "Programming as Theory Building" argues that a program is not its source code. A program is a shared mental construct (he uses the word theory) that lives in the minds of the people who work on it. If you lose the people, you lose the program. The code is merely a written representation of the program, and it's lossy, so you can't reconstruct

@jpjacobs
jpjacobs / som.ijs
Last active Feb 29, 2016
Kohonen SOM
View som.ijs
NB. Self-Organising map
require 'math/lapack/geev'
require 'tables/csv'
require 'viewmat'
NB. closeall_jviewmat_ ''
NB. parameters:
N =: 30 NB. side of neuron map. (N -> (*:N) neurons)
ntrain =: 25 NB. number of training samples per class
niter =: 10000 NB. number of iterations
'a0 an' =: 25 1 NB. Starting and ending learning factor
@adrian17
adrian17 / whence.ijs
Last active Aug 29, 2015
whence for J
View whence.ijs
whence =: verb define
select. 4!:0 < y
case. _2 do. 'invalid name'
case. _1 do. 'name not defined'
case. 0;1;2;3 do.
index =. 4!:4 < y
select. * >: index
case. 0 do. 'name defined locally'
case. 1 do. > index { 4!:3''
end.
@adrian17
adrian17 / collatz.ijs
Last active Aug 29, 2015
collatz fractal in J
View collatz.ijs
load 'viewmat'
gen_table =: 4 : '(0j1*(i: x)) +/ i: y'
fractal =: 1 : 0
:
x u"0 (y +~ 30000 %~ 150 gen_table 150) NB. resolution and scale, not sure how to decouple them
)
collatz =: 4 %~ 2 + (7*]) - (2+5*])* 2 o. o.
is_bounded_c =: 4 : '((0: collatz^:x) :: 1:) y' NB. collatz
@adrian17
adrian17 / sudoku.ijs
Created Mar 5, 2015
sudoku in J (translation of APL algorithm)
View sudoku.ijs
s44 =: 4 4 $ 0 0 0 0 0 0 2 1 3 0 0 4 0 0 0 0
box =: (] #"1 ] # ([: i. 2 # ]))
indices =: 3 : 0
yy =. {. y
a =. yy #"0 i. yy
b =. |: a
c =. a ,/"0 b
)
@Twinklebear
Twinklebear / fragment.glsl
Last active Aug 29, 2015
Instanced textured quads, produces this render: https://i.imgur.com/opgHu0x.png
View fragment.glsl
#version 330 core
//Sampler defaults to unit 0 which is where our texture is bound
uniform sampler2D tex;
in vec2 fuv;
out vec4 color;
void main(void){
View j-vs-hs.md
h> (map sum)[[0..n]|n<-[0..10]
j] +/"1 i."0 >:i.11


j] +~^:5]1
h> let rfx f y = f y y ; pow = (\n f -> if n == 0 then id else f . pow (n-1) f) in pow 5 (rfx (+)) 1 

j] +/~i.4
@tangentstorm
tangentstorm / something4thy.js
Created Aug 2, 2013
something 4thy this way comes...
View something4thy.js
var b4 = (new function() { var EOF='\0',self = {
d:[], a:[], // data and auxiliary/return stack
defs:[],core:[],scope:[], // dictionary
base:10, // numbers
cp:-1, ch:'\x01',ibuf:[],wd:'', // lexer state
compiling:false,state:[],target:[], // compiler state
def : function (k,v){
var res=self.defs.length; self.defs.push(v); self.scope[0].push([k,res]); return res },
View serial.go
type Message struct {
type string
midiData [3]byte
sysexData[255]byte
sysexLen int
}
func NewBoard() *Board {
b := &Board{}
// Start the message loops
@alexaltair
alexaltair / Today's Learning.md
Last active Dec 18, 2015
An exploration of infinite lists.
View Today's Learning.md

The first thing that really surprised me today was the flexibility of Ruby's shovel operator, <<. A student in the class had tried the following:

a = [0]
a << a

What do you think a is now? I was sure it would be [0, [0]]. But lo and behold, Ruby sparkles;

a = [0]
a << a
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