> Unless I'm mistaken, picking off the top bits results in truncation
> and not rounding. If it matter in your application, you need to add
> one half in whatever your fraction units are, before you pick off the
> top bits. Otherwise, your results will all be biased 1/2 unit down
> on the average.

You are correct if you really want to round to the nearest integer.
However, many times the representation is such that you actually want to
truncate.  In fact, this often comes naturally and is sometimes a good idea
to make happen deliberately.  In this scheme you replicate the high bits
into the fraction bits when expanding a number, but just truncate to convert
back to the best integer value.


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