2024-09-25

[bg] Фото-трофей

Tramvialis tatrensis serdicensis,
разред Релсови,
клас Колесни,
царство Градска мобилност
в естествената си среда (in the wild).

Още един хубав ден в Сердика!

[EN] The Fine Day Positive Feedback Loop

It is a fine day and I am full of the milk of human kindness.
I am full of the milk of human kindness and it is a fine day.

_________
I argue that post hoc sed non propter hoc does not necessarily apply to cybernetics.

2024-09-24

[bg] Три епиграми от Радой Ралин

1 Шекспир и режисьорите

Тези, дето го познават,
го пресътворяват.
Тези, що не му отбират,
го интерпретират.


2

Бе Владимиров назначен
културен аташе в Аден.
Едва тогава той узна,
че имало такваз страна.


3

Хубавата епиграма
се разказва между двама.
А която е половинчата,
се печата.

[EN;bg] What kind of software professionals? *** Какви софтуерни професионалисти?

We call ourselves software engineers, but we are actually software mechanics, arms to the elbows covered in virtual grease...
***
Наричаме себе си софтуерни инженери, но всъщност сме софтуерни механици, с ръце, покрити до лактите с виртуална смазка...

2024-09-23

[EN] Limericks 1–4

1 (remember the hurricane?)

A windy lady called Irene
Is visiting the East Coast scene.
Over weather extreme
She is reigning supreme
Recalling the mom of the porphyrogene.

(2011-08-28)


2 (remember the hurricane?)

An energetic young lady called Sandy
Has come, a tad early, for candy.
She treats us with tricks
And some rather high kicks,
Does a very "good" job, naughty Sandy.

(2012-10-29)


3

There was an infinite loop in New Jersey
That had to be killed without mercy.
But the syscall got blocked
And the tty got locked—
There is, and will be, divergence in Jersey.


4 (over-alliterated)

A truculent teen in Tyrol
Joined a few Facebook fora last fall.
She is both very bright
And not averse to a fight:
Now she’s trawling for trolls in Tyrol.



[EN] SI to fur/ftn (units & values)

(defconstant fur (* 220 3 12 254/100 1/100)
  "A furlong, 220 yards (m).")

(defconstant ftn (* 14 24 3600)
  "A fortnight (s).")

(defun fur/ftn (v)
  "Convert m/s to furlong/fortnight.
Exactly for an exact argument."
  (/ v (/ fur ftn)))

(fur/ftn 1) ;unit
6.012885e+3
(let ((u (/ fur ftn)))
  `(,(float u) ,(fur/ftn u))) ;unit
(1.6630952e-4 1)
(fur/ftn (/ 5e3 3600)) ;typical human walking
8.351229e+3
(fur/ftn (* 7.6 1852 1/3600)) ;typical WW2 U-boot (submerged)
2.3509045e+4
(fur/ftn (* 17.7 1852 1/3600)) ;typical WW2 U-boot (surface)
5.475133e+4
(fur/ftn (/ 120e3 3600)) ;typical speed limit (divided highway)
2.0042948e+5
(fur/ftn 335) ;typical Mach 1: standard day, sea level (NASA; 1100 ft/s)
2.0143164e+6
(fur/ftn 11.186e3) ;Earth escape velocity
6.726013e+7
(fur/ftn 299792458) ;light
1.8026175e+12

See also:

_________
The above was produced with the help of the following (something of a rarity where casual use of EVAL is more or less warranted):

(with-open-file (out "/storage/emulated/0/Documents/fur-ftn.txt" :direction :output :if-exists :supersede)
  (loop with *print-case* = ':downcase
    for x in '(
((fur/ftn 1)
 "unit")
((let ((u (/ fur ftn)))
  `(,(float u) ,(fur/ftn u)))
 "unit")
((fur/ftn (/ 5e3 3600))
 "typical human walking")
((fur/ftn (* 7.6 1852 1/3600))
 "typical WW2 U-boot (submerged)")
((fur/ftn (* 17.7 1852 1/3600))
 "typical WW2 U-boot (surface)")
((fur/ftn (/ 120e3 3600))
 "typical speed limit (divided highway)")
((fur/ftn 335)
 "typical Mach 1: standard day, sea level (NASA; 1100 ft/s)")
((fur/ftn 11.186e3)
 "Earth escape velocity")
((fur/ftn 299792458)
 "light")
)
  do
  (format out "~S ;~A~%~E~%"
                       (first x)
                       (second x)
                       (eval (first x)))))


[EN] Performance of 'Naive' Ratio Addition

;;;; -*- mode: lisp -*- ;;; Explore the performance of 'naive' ratio addition. ;;; Evaluate (time-addition 17000) ;;; to compare tha...