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Dalia Sobhy 2012-11-10, 22:11
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Ted Yu 2012-11-10, 22:25
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Dalia Sobhy 2012-11-11, 16:07
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Re: Question
Dalia:
If you look at:
public interface ColumnInterpreter<T, S> {

you would see:
 * @param <T> Cell value data type
 * @param <S> Promoted data type

S can represent sum of values of T. The rationale was that aggregation of
one type (integer, e.g.) may have to be represented by another type
(double, e.g.)

>From this blog you can get some history on this subject:
http://zhihongyu.blogspot.com/2011/03/genericizing-endpointcoprocessor.html

For row counting, it is already implemented:
  public <T, S> long getRowNum(ColumnInterpreter<T, S> ci, Scan scan)
You can embed your filter in scan object.

Cheers

On Sun, Nov 11, 2012 at 8:07 AM, Dalia Sobhy <[EMAIL PROTECTED]>wrote:

>
>
> Thanks Ted :D
>
> But can anyone explain to me this sentence:
>
> ColumnInterpreter<T, S> ci
>
> How to set a ColumnInterpreter ?? What is T and Whats S?
>
> I want to perform average on an Aggregationclient, so could anyone provide
> me with a sample code?
>
> Also if i want to count the number of rows which has a specific value ?
> What to use Filters or AggregationClient?
>
> Thanks in advance,
>
> > Date: Sat, 10 Nov 2012 14:25:22 -0800
> > Subject: Re: Question
> > From: [EMAIL PROTECTED]
> > To: [EMAIL PROTECTED]
> >
> > Take a look at AggregationClient.java and TestAggregateProtocol.java
> >
> > Cheers
> >
> > On Sat, Nov 10, 2012 at 2:11 PM, Dalia Sobhy <[EMAIL PROTECTED]
> >wrote:
> >
> > >
> > > Dear all,
> > >
> > > I want to use the aggregate functions, but do anyone have a code or
> sth to
> > > understand them ..
> > >
> > > Thanks
> > >
> > > Best Regards
> > > Dalia
> > >
>
>
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Dalia Sobhy 2012-11-11, 19:42
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yuzhihong@... 2012-11-11, 20:31
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Dalia Sobhy 2012-11-13, 22:14
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Ted Yu 2012-11-13, 22:29
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Dalia Sobhy 2012-11-14, 09:09
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Dalia Sobhy 2012-11-15, 00:07
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Ted Yu 2012-11-15, 00:22