Javier,

I want to expand upon what I said; you might already get this point but
others may come along and read this and might not.

Naturally you are using a 2D map as most applications do (Google Earth is
the stand-out exception), and fundamentally this means the map is projected
-- it has to be.  There isn't a "right" (correct) projection, generally
speaking.  Most/all web based map APIs are strictly "web mercator".  If you
have a map GUI selection tool in which a circle is drawn, a perfect looking
round circle, then it's a lie unless you're looking directly at the equator. 
If the intent is for the user to draw a distance based circle, then ideally
your map tool should draw an elliptical looking circle if it's to be
accurate.  This is why you got confused; you saw a circle yet the point
wasn't drawn in the circle because that circle *should have been* stretched
vertically to barely pass it.  If on the other hand you intend for the query
shape to be exactly what it displays to be (what appears to be a perfect
circle), even though this means the true geodetic shape is not a perfect
circle, then you could use geo="false" (and configure some other attributes)
such that you are using standard planar math, not geodetic.  Then your query
shape would appear to work correctly but IMO its misleading over the first
option (draw an ellipse, not a circle).  The circle misleads the user; it
mislead you.

~ David


Javier Molina wrote
> Hi David,
> 
> As it happens the points are using the right projection, I can see them in
> the same position using the page you just provided.
> 
> There is something wrong with the radius of the circle though I need to
> investigate that but it is a relief to know that there is nothing wrong
> with Solr and that I didn't mix the concepts, it is just as in many cases
> the problem is somewhere else where you would never imagine.
> 
> Thanks for the hint.
> 
> Cheers,
> Javier
> 
> 
> 
> 
> 
> On 11 December 2012 02:47, David Smiley (@MITRE.org) <

> DSMILEY@

> >wrote:
> 
>> Javi,
>>   The center point of your query circle and the indexed point is just
>> under
>> 49.9km (just under your query radius); this is why it matched.  I plugged
>> in
>> your numbers here:
>> http://www.movable-type.co.uk/scripts/latlong.html
>> Perhaps you are misled by the projection you are using to view the map,
>> on
>> how far away the points are.
>>
>> FYI The default distErrPct of 0.025 should be fine in general and wasn't
>> the
>> issue.  You should (almost) never use 0.0 on the field type because that
>> means your indexed non-point shapes (rectangles you said) will use a ton
>> of
>> indexed terms unless they are very small rectangles (relative to your
>> grid
>> resolution -- 1 meter in your case).  Using distErrPct=0 in the query is
>> safe, on the other hand.
>>
>> Cheers,
>>   David
>>
>>
>>
>> -----
>>  Author:
>> http://www.packtpub.com/apache-solr-3-enterprise-search-server/book
>> --
>> View this message in context:
>> http://lucene.472066.n3.nabble.com/Intersect-Circle-is-matching-points-way-outside-the-radius-Solr-4-Spatial-tp4025609p4025704.html
>> Sent from the Solr - User mailing list archive at Nabble.com.
>>





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