My focus is at the moment on the colt-derived code. I'll report in
when I get that far.

On Tue, Dec 15, 2009 at 10:10 AM, Sean Owen <[email protected]> wrote:
> There are other solutions that aren't too expensive like maintaining a
> bit set of entries that are valid (which is fast since it initializes
> to all false/0). I've got a fast implementation in the code already.
> I'd prefer to not let the performance consideration convince us to not
> implement the semantics that seem correct -- if we agree that NaN is
> 'correct'.
>
> On Tue, Dec 15, 2009 at 2:57 PM, Benson Margulies <[email protected]> 
> wrote:
>> I had better be more clear. The problem is that Arrays.fill does use
>> some time. If you just say new double[1000], you've got 0. To get NaN,
>> you then need a fill. Last summer, when I was trying to get an E+M
>> procedure to run in reasonable time, and trying to initialize many
>> arrays  with NaNs to detect various errors, I measured and found that
>> I was getting killed. Now, does that mean that at construction and
>> resize of these hash tables that we can't afford the fill? I won't
>> make that claim without a measurement.
>

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