# Feature question

**URL:** <https://www.ruby-forum.com/t/feature-question/138064>\
**Category:** Ferret\
**Created:** [May 19, 2008, 11:15pm UTC](https://www.ruby-forum.com/t/feature-question/138064 "2008-05-19T23:15:46Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![arvias](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ac91a4/32.png) [@arvias](https://www.ruby-forum.com/u/arvias)\
**Post date:** [May 19, 2008, 11:15pm UTC](https://www.ruby-forum.com/t/feature-question/138064/1 "2008-05-19T23:15:46Z")

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Hi,

Can ferret search for a combination of words and return the distance  
between them in a text? If it exists is there a way you can improve on  
this by looking if they are separated by a certain character(like . for  
different sentences)?

Thanks,  
Radu

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<div class="post-metadata">

**Author:** ![arvias](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ac91a4/32.png) [@arvias](https://www.ruby-forum.com/u/arvias)\
**Post date:** [May 19, 2008, 11:34pm UTC](https://www.ruby-forum.com/t/feature-question/138064/2 "2008-05-19T23:34:32Z")

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Hi!

On 19.05.2008, at 22:46, Radu S. wrote:

> Hi,
> 
> Can ferret search for a combination of words and return the distance  
> between them in a text?

It won’t directly return you the distance but given the fact that  
Ferret stores term positions it should be possible to manually  
determine the distance between different terms. You may also issue  
phrase queries that only return hits for terms that are separated by  
at most n other terms. The QueryParser API docs or the Ferret book  
have examples of this.

> If it exists is there a way you can improve on this by looking if  
> they are separated by a certain character(like . for different  
> sentences)?

Usually you dont index characters like ‘.’ at all (they are removed  
during analysis, when the text is split up into tokens), but if you  
changed that so sentence endings end up in the index as kind of  
special terms this might be possible, too.

I dont know your use case, but keep in mind that you can get the  
effect of ranking terms that are closer together higher by chaining  
Phrase Queries with different Slop values, and assigning them  
different boosts:

(“red fox”)^15 OR (“red fox”~4)^10 OR (“red fox”~10)^5 OR (“red  
fox”~100)

this will boost the exact match the most, and assign lower boosts to  
matches where the terms have larger distance.  
Maybe something like this will already be a ‘good enough’ solution to  
your problem?

cheers,  
Jens

–  
Jens Krämer  
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VAT Id DE251962952  
[http://www.jkraemer.net/](http://www.jkraemer.net/) - Blog  
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