On 2009-03-03 23:23, Thomas Stover wrote: > > -I'm curious what NaNAware is, but I haven't found a good link > explaining it.
Hello Thomas, NaNAware refers to one of the special "numbers" in IEEE arithmetics: NaN is the acronym of Not-a-Number, it is used to represent the result of 0.0/0.0, sqrt(-1) etc. Using such special numbers (Infinity is another one) makes the floating arithmetical system a closed system, that is: every possible combination of x, y and +,-,*,/, etc. has a value. (The upshot of that characteristic of IEEE arithmetics is that the underlying hardware does not have to raise exceptions.) One peculiar property of NaN is that it is unequal to any number, even unequal to itself: NaN != NaN. That said, NaNs can be used to represent missing values, as is done in the CSA and NN libraries. But software support for dealing with NaNs is not always obvious, hence the test for NaNs in the CMake files. (I do not know of a concise publication that explains these features and more, but with the keywords above you can probably dig up tons of stuff :)) Regards, Arjen Delft Hydraulics, GeoDelft, the Subsurface and Groundwater unit of TNO and parts of Rijkswaterstaat have joined forces in a new independent institute for delta technology, Deltares. Deltares combines knowledge and experience in the field of water, soil and the subsurface. We provide innovative solutions to make living in deltas, coastal areas and river basins safe, clean and sustainable. DISCLAIMER: This message is intended exclusively for the addressee(s) and may contain confidential and privileged information. If you are not the intended recipient please notify the sender immediately and destroy this message. Unauthorized use, disclosure or copying of this message is strictly prohibited. The foundation 'Stichting Deltares', which has its seat at Delft, The Netherlands, Commercial Registration Number 41146461, is not liable in any way whatsoever for consequences and/or damages resulting from the improper, incomplete and untimely dispatch, receipt and/or content of this e-mail. ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ Plplot-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/plplot-devel
