There are 2 perfect squares each rotation of the spiral. ⌊(⌈⍵*÷2)÷2 is a Chebyshev distance of ⍵ to origin, i.e. the absolute value of larger coordinate. To get the other, subtract that square and do some modular magic dance (there are 4 zeros at each layer, and 4 max values at turning points where both coordinates are equal), and just add the two together.
{(|k-(2×k)|⍵-(1+k×2)*2) + k←⌊(⌈⍵*÷2)÷2 ;k} 277678
(That ;k is GNU APL notation for local variable, just remove it for Dyalog).
| #!/bin/sh | |
| # Bare-bones Tk GUI for ABX testing. | |
| # klg, Nov 2017; next line executed by sh \ | |
| exec wish "$0" ${1+"$@"} | |
| package require Tk | |
| package require msgcat | |
| namespace import msgcat::mc | |
| # Require k of n trials to pass | |
| lassign {13 16} abx_k abx_n |
| #!/usr/bin/env perl | |
| # List or edit comments in RFC 7845 Ogg Opus files. | |
| # klg, Nov 2017 | |
| use strict; | |
| package Ogg::Page { | |
| use strict; | |
| use Carp; | |
| use Digest::CRC; |
| #!/usr/bin/env perl | |
| # Show combined changelog for the whole dpkg-based system. | |
| # klg, Nov 2017 | |
| use strict; | |
| use File::ReadBackwards; | |
| use Dpkg::Version 'version_compare'; | |
| use Dpkg::Changelog::Debian; | |
| open \*STDOUT, '|-', $ENV{PAGER} || 'pager' if -t; |
| use utf8; | |
| use Unicode::Normalize; | |
| # Expand horizontal Kana iteration marks | |
| # 例: いすゞ→いすず ところゞゝゝ→ところどころ | |
| sub expand_kanaiter { | |
| local $_ = NFKD($_[0]); | |
| s{( | |
| [あ-んア-ンー][\x{3099}\x{309a}]? | |
| (|(?1)) |
| #!/usr/bin/env perl | |
| # Strip non-essential markers from JPEG data and output bare JIF file | |
| # (which might not actually be suitable for interchange because of missing | |
| # color space information, subsampling geometry, and whatnot). | |
| # klg, Sep 2017 | |
| use strict; | |
| my @M; | |
| { | |
| my $buf = ''; |
| # Emit signals when tmux session is attached or detached. | |
| # klg, May 2017 | |
| use strict; | |
| use Irssi; | |
| use POSIX 'mkfifo'; | |
| Irssi::signal_register { | |
| 'tmux attached' => ['int'], | |
| 'tmux detached' => ['int'] | |
| }; |
| # Bet in Rizon lottery | |
| # <https://wiki.rizon.net/index.php?title=Vizon> | |
| # klg, May 2017 | |
| use strict; | |
| use Irssi; | |
| use List::Util 'shuffle'; | |
| my $server_tag = 'Rizon'; | |
| my $vizon_nick = 'VIzon'; |
| #!/bin/sh | |
| # Execute a window manager but allow changing it easily at run time. | |
| # Requires sufficiently dumb WM that eofs on exit (beware of its children | |
| # sharing standard output) and leaves sane state when simply killed. | |
| # klg, Mar 2017 | |
| # \ | |
| exec wish "$0" "$@" | |
| package require Tk | |
| wm withdraw . |
| #!/usr/bin/es -- | |
| # Password-based encryption with GPG2 | |
| # klg, Dec 2016 | |
| fn easkpass { | |
| * = $* 'Password: ' | |
| <>/dev/tty >[1=0] let ( | |
| g = `{stty -g} | |
| ) | |
| unwind-protect { |