[postgis-users] Bounding Circle instead of Bounding Box

[Shane Spencer]

indeed, you could even pregenerate the correct ellipse geometry then use
that with ST_DWithin.  At least if you have an ellipse instead of a true
circle.

Shane

On 9/9/07, Paul Ramsey <pramsey at refractions.net> wrote:
>
> Indeed:
>
> SELECT *
> FROM mytable
> WHERE
>    ST_DWithin(mytable.the_geom, ST_SetSRID(MakePoint($x, $y), $srid),
> $distance);
>
> P.
>
> On 9-Sep-07, at 11:25 AM, Shane Spencer wrote:
>
> > I don't understand how the Distance() and Intersects() and Contains
> > () function wouldn't work for this?
> >
> > Are X and Y radius the same?
> >
> > On 9/9/07, postgis at jochem.name <postgis at jochem.name > wrote:Hi,
> >
> > what I want to do is finding certain features in some distance
> > around a
> > certain point. Those features should be located in some corridor
> > between X
> > and Y km around this point. Currently I've solved this problem by
> > computing two bounding boxes of X and Y km around the point and
> > taking the
> > difference of those. So far so good.
> >
> > But I don't want to have some quadratic box but a real circle - is
> > there
> > any way to achieve this?
> >
> > Best regards,
> > Rainer
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