Hi Shirley, Yes, but I don't know a single case where the use of sNaNs is more apropiate than qNaNs, maybe for debugging purpouses...
It's also important that the IEEE 754-2008 revision specified the encoding of sNaNs but some architectures are not compatible with the standard. I prefeer to use quiet NaNs so I can let them propagate through the code when is convenient and launch an exception manually when is really necessary. Simple, compatible and flexible. Of course, this is only my personal preference.
