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From Dimitri Pourbaix <pourb...@astro.ulb.ac.be>
Subject Re: [math] speeding up percentile based statistics
Date Sat, 18 Sep 2010 18:43:43 GMT
Luc,

>> On the other hand, the speed-up version would no longer
>> be mathematically correct, as a rough approximate of the pivot would be
>> adopted.
>
> No, the exact pivot is used. Its evaluation is only delayed. It would be
> correct.

Given a **general** array, I do not think one can identify the median in
just n iterations (i.e. reading the array only once).

Dim.
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