Re: [OT] Re: GSOC2014 Application: High Precision Arithmetic Computation

[CdeMills]

Susi Lehtola wrote
> Actually, I don't think so. Because of the chaotic nature of the
> equations, slight differences in the starting conditions lead to vastly
> different solutions given enough time.

Hello Susi, 

thanks for your input. Weather systems are indeed chaotic. What we intend to
solve are systems where the RELATIVE accuracy is maintained over many
ranges. Two examples:
-semi-conductors: tests are performed over 10 decades of currents, with
autoranging on. So each measurement is given with an accuracy of around .1
%; yet mixing nano-amps and amps is not very comfortable.
-chemicals systems, in particular plasma: you have state transitions in
cascade, like f.i molecule => ions +1e- => ions with two lost electrons; or
molecule => atoms. The transition probabilities are small; yet the different
populations can be measured by different techniques with comparable
accuracies.

What we wish to solve are situations where the numerical noise on the values
with the highest magnitude becomes comparable to the magnitude of the
smallest components. In the case of semi-conductors or plasma, those
minority components are responsible for the interesting behaviours:
conduction or light generation.

Regards

Pascal



--
View this message in context: 
http://octave.1599824.n4.nabble.com/GSOC2014-Application-High-Precision-Arithmetic-Computation-tp4663190p4663194.html
Sent from the Octave - Maintainers mailing list archive at Nabble.com.