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Re: [Phys-L] timestamps ... related to Timing Statistic

This is a roughly comparable situation to that raised recently on phys-l, namely, modeling the spin down of a then-current fad, the  spinner toy ( not to mention the issue of modeling a pendulum,. which is also a period measuring setup.)
In those earlier scenarios, it was interesting to extend the model to the lowest possible angular frequencies where stiction etc. causes noticeable inflexions in the decay curve. there, eight places of precision was available until the penultimate [part] period: here eight place time precision ceases at angular rates less than 2 pi rads/sec and longer period data is discarded.
So? Horses for Courses!

Brian W
(for some reason, I was unable to inspect the actual experimental data saved onto a google 'cloud'. Pity!)

On 11/9/2018 4:51 PM, John Denker via Phys-l wrote:
Here is what typical timestamped data looks like.

Suppose you have a disk that goes around π*e times per
second, i.e. about 8.54 times per second. You could
record every time it comes around, but suppose you
don't want to. Suppose you prefer to have data points
spaced *approximately* one second apart. So wait until
the beginning of the next whole second, then timestamp
the next event (i.e. the start of the next cycle).
Keep a bazillion guard digits on the timestamp.

Using this procedure, the cycle numbers are exact,
and the timestamps have negligible roundoff error.
The spacing between timestamps is not quite even,
but is as even as it can be without damaging the
data.

timestamp cycle #

0.000000 0
1.053897 9
2.107794 18
3.044591 26
4.098488 35
5.035286 43
6.089182 52
7.025980 60
8.079877 69
9.016674 77
10.070571 86
11.007368 94
12.061265 103
13.115162 112
14.051960 120
15.105857 129
16.042654 137
17.096551 146
18.033348 154
19.087245 163
20.024042 171
21.077939 180
22.014737 188
23.068634 197
24.005431 205
25.059328 214
26.113225 223
27.050022 231
28.103919 240
29.040716 248
30.094613 257
31.031411 265
32.085308 274
33.022105 282
34.076002 291
35.012799 299
36.066696 308
37.003494 316
38.057390 325
39.111287 334
40.048085 342

To see how this was done:
https://www.av8n.com/physics/timestamp.gnumeric
https://www.av8n.com/physics/timestamp.xls


If you absolutely insist on data that is evenly spaced in
time, start with the timestamped data in all its glory, then
fit it to a physically-correct model, then use the model
to generate whatever you want.

The Vernier instrument presumably tries to interpolate,
but it cannot possibly do so properly, because it has no
idea how to model your data. Any interpolation scheme
that works OK for your situation will fail miserably in
somebody else's situation, and vice versa.
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