"Jan Karman" <*axy*@[EMAIL PROTECTED]
> wrote in message
news:476f7998$0$25477$ba620dc5@[EMAIL PROTECTED]
>
> "Morten Kromberg" <mkrom@[EMAIL PROTECTED]
> wrote in message
>
news:fb1bc6db-0645-4c45-b7a9-ea9682c58356@[EMAIL PROTECTED]
> On Dec 22, 10:59 pm, "Jan Karman" <*a...@[EMAIL PROTECTED]
> wrote:
> Sometimes there's also an individual use. E.g. when playing FreeCell, I
liked
> to
> know how many games I had to win before the score was increasing: I love
APL!!
>
> Now I have this story: I recently bought an 20-years-or-so old
harpsichord,
> from
> a church-choir. One probably knows the things about collective
possession on
> the
> one hand and collective maintenance on the other. It was totally
neglected.
> I'm
> now trying to get back the old state and quality (it's an exact copy of
the
> Baffo harpsichord in the Paris Musée de Musique, built by a reknowned
Belgian
> harpsichord-maker).
>
> Now, what is the ideal thickness of the strings, that is to say, of each
> string?
> Here's Taylor's formula, in K, that is: (for typing convenience, but
which can
> be litterally replaced by APL-primitives)
>
> d:(% f * l) * (T % p * pi % g) ^ 0.5
>
> in which d = thickness
> f = frequency in Herz
> l = length of string in metres
> T = string tension in kg weight
> g = acceleration of gravity = 9.8 m/sec²
>
> What is the difference when tuning on a1 = 440 or a1 = 415?
>
> With APL it's easy to find the "ideal" average for re-stringing the
entire
> instrument at every thinkable frequency.
> I love APL!!
While re-stringing I wondered how long the rest of the bundle continuous
string
would be. From physics we know that it is hidden in the weight. length x
surface
of cross-section = content. Content = weight : specific gravity. So length
=
content : surface.
Thanks to the logfile in Dyalog APL I could reproduce the process. I got:
(0.042÷8.4)÷({circle}1)×0.125*2
(42 grams of yellow copper, diameter 0.25 mm) and APL was of much help.
Of course this is a trivial problem & process, but we must never forget
that APL
has been designed from the need for a unique & concise means for
communicating
processes in math & physics (see Iverson's APL Source Book & Knuth's The
Art of
Computer Programming).
ps.
On the first day of this new year I have to apologize for my "gibberish"
as in
"reknowned". But since we could spell FISH as GHOTI (Shaw) I may probably
be excused. Besides I couldn't find REKNOWN in the dictionary, since the
"k"
has disappeared on the road - presuming that RENOWN has been deducted
from KNOW, not from NOW.
Happy New Year!
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