mahout-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Paulo Villegas <pa...@tid.es>
Subject Re: Contract for DataModel methods getUserIDs & getItemIDs
Date Wed, 14 Nov 2012 21:12:42 GMT
Ok, thanks for the info. I'll try and see.

If it wasn't really necessary, maybe those javadoc comments could be
removed from the file, to avoid unnecessary processing. But they come
from far away. I've checked the history of the file and they were
already there (with slightly different wording) 5 years ago, at the time
of "MAHOUT-37: initial commit of contributed Taste code"




> Off the top of my head, I can't think of a place that really needs this
> behavior. It would come up, likely, in contexts where two models get merged
> for some reason and it's doing a merge of ordered lists. I searched some
> likely places and did not see this being used this way. My hunch is that
> you will get away with it.
>
>
> On Wed, Nov 14, 2012 at 6:10 PM, Paulo Villegas <paulo@tid.es> wrote:
>
>> Hi. The DataModel interface in org.apache.mahout.cf.taste.**model
>> specifies in the documentation for the methods getUserIDs & getItemIDs
>>
>>
>>    all {user,item} IDs in the model, in order
>>
>> My question is: is the "in order" specification a standing requirement?
>> I've browsed casually through the source and it seems there is no need
>> for the iterator to return IDs in order (the uses I saw just iterate
>> through the values apparently with no requirement for them to be
>> inorder). But the code base is big, so I may have missed places where it
>> is actually needed.
>>
>> The reason I ask is that I'm implementing a custom DataModel for our
>> purposes, which can be updated on the fly without rebuilding, and the
>> need to return the IDs in order is somehow inconvenient, since it
>> affects efficiency. If I could get away without ordering, it would be
>> much better.
>>
>> Thanks
>>
>> Paulo
>>
>>
>> ______________________________**__
>>
>> Este mensaje se dirige exclusivamente a su destinatario. Puede consultar
>> nuestra política de envío y recepción de correo electrónico en el enlace
>> situado más abajo.
>> This message is intended exclusively for its addressee. We only send and
>> receive email on the basis of the terms set out at:
>> http://www.tid.es/ES/PAGINAS/**disclaimer.aspx<http://www.tid.es/ES/PAGINAS/disclaimer.aspx>
>>
>


________________________________

Este mensaje se dirige exclusivamente a su destinatario. Puede consultar nuestra política
de envío y recepción de correo electrónico en el enlace situado más abajo.
This message is intended exclusively for its addressee. We only send and receive email on
the basis of the terms set out at:
http://www.tid.es/ES/PAGINAS/disclaimer.aspx

Mime
View raw message