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RichardBarrell / gist:941565a570729339240e
Created August 7, 2014 00:26
__reduce__ gets used by pickle and cPickle, when defined by regular Python classes
>>> import pickle
>>> class C(object):
... def __init__(self, banana):
... self.banana = banana
... def __reduce__(self):
... return (C, (self.banana,))
...
>>> pickle.dumps(C(1))
'c__main__\nC\np0\n(I1\ntp1\nRp2\n.'
>>> pickle.loads(pickle.dumps(C(1)))
@RichardBarrell
RichardBarrell / gist:a33a5dcaa022ba784cf7
Created August 10, 2014 14:51
Watching the PCI registers in /sys/ while switching my 3d card on and off 😸
RichardB@narcissus ~$ od -t x1 /sys/bus/pci/devices/0000:01:00.0/config
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0000100
RichardB@narcissus ~$ optirun glxgears >/dev/null &
[1] 3758
RichardB@narcissus ~$ sleep 1
RichardB@narcissus ~$ od -t x1 /sys/bus/pci/devices/0000:01:00.0/config
0000000 de 10 92 13 07 00 10 00 a2 00 02 03 00 00 00 00
0000020 00 00 00 f6 0c 00 00 e0 00 00 00 00 0c 00 00 f0
@RichardBarrell
RichardBarrell / silly_bars.html
Created October 9, 2014 00:06
<!doctype html>
<html><head><meta charset="UTF-8" />
<title>Odd layout example.</title>
<style type="text/css">
#evil-container {
position: relative;
background: #aaffaa;
}
body, #evil-container {
width: 100%;
@RichardBarrell
RichardBarrell / FindBirthday.hs
Created October 23, 2014 13:32
module FindBirthday where
-- compile as: ghc --make FindBirthday.hs -main-is FindBirthday.main
-- or run as: runhaskell FindBirthday.hs
-- and answer "y" or "n" when the program asks you a question. :)
import Data.Time (formatTime, addDays)
import System.Locale (defaultTimeLocale)
-- use 2014 because that was a leap year, and we need all 366 days.
@RichardBarrell
RichardBarrell / Cargo.toml
Created October 31, 2014 12:40
[package]
name = "ie_counts"
version = "0.0.1"
authors = ["Richard Barrell <[email protected]>"]
[[bin]]
name = "ie_counts"
crate-type = ["staticlib"]
@RichardBarrell
RichardBarrell / bash_profile
Created July 7, 2015 11:02
# setting ALTERNATE_EDITOR to the empty string "" instructs
# emacsclient to invoke Emacs in daemon-mode iff it isn't running already
export EDITOR=emacsclient
export ALTERNATE_EDITOR=""
@RichardBarrell
RichardBarrell / PrimeLastDigit.hs
Created September 18, 2015 16:11
looks like a roughly even split between 1,3,7,9 up to the millionth prime. I got bored waiting for 10 million to finish.
module PrimeLastDigit where
-- compile with:
-- ghc --make PrimeLastDigit.hs -O2 -main-is PrimeLastDigit.main
import Data.List (foldl')
primes :: [Integer]
primes = 2 : [ c | c <- [3,5..], all (\p -> c `mod` p > 0) (takeWhile (\p -> p*p <= c) primes) ]
@RichardBarrell
RichardBarrell / Collatz.hs
Created December 15, 2015 21:49
see https://lobste.rs/s/xf6yfw/calculating_integer_factorials_in_constant_time_taking_advantage_of_overflow_behavior/comments/jnzup5#c_jnzup5
{-# LANGUAGE BangPatterns #-}
module Collatz where
-- thing I want to know: what's the smallest (n) such that a naive C
-- implementation of "iterate the Collatz function until I get to 1" with
-- fixed-size integers will encounter an integer overflow
-- the below is terrible and contains multiple implementations because I kept
-- trying to make it go faster.
import Data.Word
@RichardBarrell
RichardBarrell / to_lines.py
Last active February 16, 2016 11:25
from StringIO import StringIO
from hypothesis import given
from hypothesis.strategies import lists, binary
def to_lines(f, _block_size=32<<10):
"""file.__iter__ but in python and ought to be slower
>>> list(to_lines(StringIO("foo\\nbar\\nbaz\\n"), _block_size=2))
['foo\\n', 'bar\\n', 'baz\\n']
@RichardBarrell
RichardBarrell / pick_csv.py
Created October 2, 2016 23:41
import csv
import sys
try:
column_indexes = list(map(int, sys.argv[1:]))
except ValueError:
sys.stderr.write("Usage: python pick_csv.py 0 1 2...\n")
sys.exit(1)
if len(column_indexes) == 0: