bug when subtracting decimals?

Petr PIKAL <petr.pikal <at> precheza.cz> writes:

Maybe that is because of Excel is so widespread now and gives expected 
results (it probably silently rounds all decimal numbers before 
calculation). 

Marc Schwartz already reminded me of that one, and it's a good point
to explicitly mention in lectures. 

I suggest to extend R by introducing %==% as "being Excellently equal".

Dieter