"Lee Harris" wrote in message
...
Where does one find out in detail about this and other Excel functions
outside Excels own help

for example, I often see formulas such as

=SUMPRODUCT(--(A1:A10=B1:B10),(C1:C10))

quoted, and one guy helped me out with this on a sheet of mine, but I have
no idea where the two "-" signs came from, how they work or how you find
out about these. Is this array arithmetic? If so, where is that detailed
in the help, or on the web?

thanks in advance
LH

See this site:
www.xldynamic.com/source/xld.SUMPRODUCT.html

Bruno