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/data/backup/$TODAY#!/bin/bash -e
read -r YESTERDAY TODAY <<<$(
python3 -c '
import datetime
def day_to_slot(n):
return bin(n)[::-1].index("1")
n = datetime.date.today().toordinal()
print(day_to_slot(n - 1))
print(day_to_slot(n))
@sinclairtarget
sinclairtarget / bernoulli.c
Created August 17, 2018 20:22
Lovelace's Note G Program in C
#include <stdio.h>
/*
* Calculates what Ada Lovelace labeled "B7", which today we would call the 8th
* Bernoulli number.
*/
int main(int argc, char* argv[])
{
// ------------------------------------------------------------------------
// Data
@rogerallen
rogerallen / .emacs
Created June 22, 2019 22:14
Simple, quick .emacs when necessary
;; Roger's Simple .emacs
;; ----------------------------------------------------------------------
;; global variables & settings
(setq auto-save-default t
auto-save-interval 1000
delete-auto-save-files nil
make-backup-files nil
require-final-newline t
compile-command "make -k "
@mmalex
mmalex / allpass.md
Last active January 22, 2025 11:57
optimising allpass reverbs by using a single shared buffer

TLDR: if you've got a bunch of delays in series, for example all-pass filters in a reverb, put them all in a single big buffer and let them crawl over each other for a perf win!

recently I was fiddling around with my hobby reverb code, in preparation for porting it onto a smaller/slower CPU. I'd implemented a loop-of-allpass filters type reverb, just like everybody else, and indeed, I basically had the classic 'OOP'ish abstraction of an 'allpass' struct that was, say, 313 samples long, and... did an allpass. on its own little float buffer[313]. (well, short integer, not float, but thats not relevant) I'll write out the code in a moment.

but then I was browsing the internet one night, as you do, and stumbled on this old post by Sean Costello of Valhalla DSP fame - noting the sad passing of Alesis founder and general all-round DSP legend, Keith Barr. https://valhalladsp.com/2010/08/25/rip-keith-barr/

It's worth a read just for his wonderful anecdote about the birth of the midiverb - which spawned the thou