0.45<0.45 = TRUE (PR#10744)

hadley wickham wrote:

It's more than that as though, as floating point addition is
no longer guaranteed to be commutative or associative, and
multiplication does not distribute over addition. Many concepts
that are clear cut in pure math become fuzzy in floating point
math - equality, singularity of matrices etc etc.

  I've just noticed that R doesn't calculate e^pi - pi as equal to 20:

  > exp(pi)-pi == 20

  [1] FALSE

  See: http://www.xkcd.com/217/

Barry

Barry,
These things fluctuate. Once upon a time (sometime in 1915 will do)
you could get $[US]4.81 for ?1.00 sterling.

One of the rare brief periods when the folks on opposite side
of the Atlantic saw i^i (to within .Machine$double.eps, which
at the time was about 0.001, if you were lucky and didn't
make a slip of the pen).

R still gets it approximately right:

  1/(1i^1i)
  [1] 4.810477+0i

$i^i = ?1

Best wishes,
Ted.

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Date: 13-Feb-08                                       Time: 15:57:02
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