8 Jan
2014
8 Jan
'14
11:34 a.m.
On Jan 8, 2014, at 12:00 PM, ARD wrote:
(Quote slightly modified)
Point taken; the TI gets very close to 2.00 for my test and should show 2.00, but for the
near-zero result, it should show the scientific-notation value it gets, not 0.00. Now I?m
curious; I?ll have to try to get my TI running long enough to try this. Hopefully Pi and
Sin are two of the keys with fewer bounce problems than the others?.and I really don?t
know what I?ll do for a battery pack. Sigh. At least the cells look like standard
Ni-Cads.
And no, although I did think about trying to write an arbitrary-precision set of
subroutines for the TI using multiple registers to represent a single number, I never did
it and 100 digits of Pi, or 100 digits of Sin(x) function, would have been beyond my
math/programming skills anyway.
- Mark
THe HP41 was a much mroe expandable ssytem than the
TI59. Or at least,
IU've never seen an TI59 controlling a benchtop of HPIB instruments,
savign the readiungs to floppy disk or tape and then trasnmittign the
logged data over an RS232 link. I do that with my HP41 all the time.
I don;t think the TI ever had a realtime clock, did it?
And of course the HP had an alphanumeric dispaly.
All true to the best of my knowledge; expandability and extensibility (sic?) was one area
where the HP was leaps and bounds ahead of the TI. I was insufficiently precise; I was
looking at total storage capacity and program execution speed as my main ?performance?
criteria at the time.
FWIW, the TI would print alpha characters on its PC-100 printer/cradle, if you had one of
those. But it was pretty kludgey, and I don?t think there?s any way to get alpha out of
the handheld part of the system. Well, OK, get the result 07734 and hold the calculator
upside down. :-)
2) I quibble
with Tony?s recommendation to reject a machine that says
Sin(Pi) = 0. I?m pretty sure the TI says that; the quicker but
essentially equivalent test I always used to taunt my HP-41-equipped
friend was (Sqrt(2))^2. The TI said 2, the HP said 1.99999? I claim
Actually, that is something rather different.
If you take a decimal approximation of SQRT(2), round it after, say, 13
digits, then square it and round the reult to 10 digits (or whatever),
you will get 2. But if you take any finite number of dgits of pi,
calculate the sin, the answer is not zero. It's of the order of
10^-(number of digits). So even if you take 13 digits of pi, the SIN
should not display as zero. I suppose you could argue that if you took
over 100 digits, the result would be zero (since a number of the order of
10^-100 will underflow to 0), but I doubt that the TI uses 100 digits
anywhere.