[R] Rounding problem R vs Excel

[Duncan Murdoch]

On 04 Jun 2003 00:24:08 -0500, you wrote:

>Excel 2002 (XP):
>
>Cell Formula          Value
>= 0.5 - 0.4 - 0.1     0.00000000000000000000E+00
>=(0.5 - 0.4 - 0.1)    -2.77555756156289000000E-17
 ...
>What is interesting is the change in the displayed value in Excel when
>the second formula is surrounded by parens (which I found purely by
>accident). This would suggest that there may be something going on in
>the parsing of the cell formula that affects the calculation and
>displayed value. 

"Interesting"?  I'd say "horrifying".  When (expr) does not evaluate
the same as expr, what can you trust?

Duncan Murdoch