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Old   May 17, 2011, 14:17
Default Quad precision?
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David Gaden
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How much trouble would it be to try implementing quad precision in OpenFOAM?

- Easy!
- Tough!
- Why would you want to try? The schemes are only "second order accurate", etc..
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Old   May 17, 2011, 14:27
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Sandeep Menon
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Are you referring to numerical precision, or something like fourth-order accuracy?
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Old   May 17, 2011, 14:49
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Need more digits! I mean using "long double", or __float128.
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Old   May 17, 2011, 14:54
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Sandeep Menon
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I've implemented an arbitrary-precision data-type as a wrap-around to the GNU MPFR library. You should be able to use this as a drop-in replacement to the scalar class:

http://www.ecs.umass.edu/%7Esmenon/t...iPrecision.tgz

However, this is still emulation in software, so don't expect blazing performance.
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Old   May 17, 2011, 15:36
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Thanks a lot, Sandeep!

I've downloaded it, and am in the process of figuring out how to use it. I'm guessing to use it in finiteVolume calculations, I need to define a new fvMatrix template specialization for a multiPrecisionScalar... fvMultiPrecisionScalar (basically identical to fvScalarMatrix).

Do you have any sample code that uses your multiPrecisionScalar class?

-Dave
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