[R] Rounding error in seq(...)

[Peter Dalgaard]

Martin Batholdy wrote:
> hum,
> 
> can you explain that a little more detailed?
> Perhaps I miss the background knowledge - but it seems just absurd to me.
> 
> 0.1+0.1+0.1 is 0.3 - there is no rounding involved, is there?
> 
> why is
> x <- 0.1 + 0.1 +0.1
> not equal to
> y <- 0.3

Remember that this is in BINARY arithmetic. It's really not any stranger 
than the fact that 1/3 + 1/3 != 2/3 in finite accuracy decimal 
arithmetic (0.33333 + 0.33333 = 0.66666 != 0.66667).

-- 
    O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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