(34C) Musical Notes (Original by J.M. Bowsher)

[Dieter]

(02-10-2019 06:15 PM)Thomas Klemm Wrote:  We could also use 55 with 1.75 instead of 440 with 4.75.
Which makes it a bit shorter.
Or then only use:

\(16.3515978313=\frac{440}{2^{4.75}}\)

Similar to the original program.

That's what I used for the mentioned HP67 program: 55/4 · √√2.

(02-10-2019 06:15 PM)Thomas Klemm Wrote:  I must admit that I still don't really understand why it shifts by an additional 50¢.

Take a look at line 67 and 121 ff. respectively of the original program. This seems to add or subtract 50 cents.

Other calculations still remain unclear to me. For instance line 017 ff. Here a tiny value of 1E–15 is added. ?!? Then both the sum and its absolute value are stored separately. Can this be negative at all? Later both (073 ff.) values are divided, so this returns the sign of that number. And there is a second occurence of a sign calculation starting at line 127. What is the purpose of that? I also wonder why line 084 ff. calculate e^x · ln 2 instead of a simple 2^x. Maybe Hans can shed some light on this.

Dieter