Hi Jianfu,
The correct place to post NCO questions is
http://sf.net/projects/nco/forums/forum/9830
Please post any followsups there.
In answer to your question, you have found a bug which is now fixed.
It was caused by NCO using the isnormal() macro to test for strange
numbers (like NaNs). Apparently isnormal() treats zero as not normal.
I did not realize that. The current NCO snapshot uses isfinite()
instead. This fixes the problem you reported. You can download/install
the current snapshot or wait for NCO 4.3.9, which will be released
real soon now. Thanks for reporting the problem!
Charlie
--
Charlie Zender, Earth System Sci. & Computer Sci.
University of California, Irvine 949-891-2429 )'(
