[time-nuts] Modified Total Deviation calculation

[Magnus Danielson]

John Miles wrote:
> If you'd like to make the C source available, I'll look at building an
> incremental version...?

If you can accept the current quick-hack state of the code (yes, I am 
not too proud of the cleanness, so no comments about coding style or the 
general uglyness), find it attached. The main goal of this code is 
correctness. Find it attached.

I'll hacking away further.

An incremental version is a trivial extention for MTOTDEV as the outer 
loop steps the 3*m sample window over the data-samples. So you need to 
keep a 3*m big backlog of samples for the largest m you need. For 
simplicity I made the expantion into the 9*m series explicit and with a 
3*m offset from the index of the original data only for clarity while 
debugging the code. Some of that debugging was not in the core 
algorithm, but in the missing 0.73 factor, which is the bias factor for 
white FM noise. A good quality measure would adjust the bias factor 
based on the dominant noise-source, but that comes as later refinement.

Anyway, hope you find the code usefull. Will hack away to make more 
values calculated. Currently the Hadamard Total Deviation is not 
correct, as a quick-check with SP1065 page 118 would tell you. But that 
was a quick-hack anyway.

Oh, yes... among the particular uglyness issues is that the routines 
know just how many samples the time or frequency sample series contains. 
Ugly as hell, but for the intended purpose (known test-series) that is ok.

Cheers,
Magnus
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