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Re: NetCDF portability and floating point translations

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  • Subject: Re: NetCDF portability and floating point translations
  • Date: Wed, 07 Dec 1994 14:18:11 -0700
> Organization: LLNL    
> Keywords: 199412072056.AA01379

Doug,

> Not to beat a dead horse, but your response raises one small question.
> If, for example, I've defined a variable to be of type NCDOUBLE (which I
> understand means IEEE 64-bit representation), but the native 64-bit
> floating point representation on a host does not match the IEEE 64-bit
> standard, do I get data (on a read) in IEEE format or the native format?

Data on a read will always be returned in the native format on which the
library has been compiled.

(My fuzzy recollection is that a double on a Cray is actually a 128-bit
representation for which there is no hardware arithmetic support and that
the Cray XDR library maps this to a 64-bit XDR double.)

--
Russ Rew                                                UCAR Unidata Program
address@hidden                                          P.O. Box 3000
http://www.unidata.ucar.edu/                          Boulder, CO 80307-3000