[postgis-users] A table of DE-9IE patterns and types of topological relations

[Martin Davis]

Is this any better?

https://postgis.net/docs/manual-dev/using_postgis_query.html#DE-9IM

On Mon, Apr 18, 2022 at 2:31 PM Jim Klassen <klassen.js at gmail.com> wrote:

> As an aside, I am noticing these graphics probably aren't very accessible
> to people with vision impairments.  There is a lack of meaningful alt-text,
> a general fuzziness/soft edges, and use of several colors of similar
> lightness.  In particular, the red is hard to separate out in grayscale and
> the red is the part that is most important as it is describing the part of
> the image that applies to that grid cell.
>
> I'm not sure if it will come through on the list, but I've converted the
> 3x3 grid image from [1] to grayscale below as an example.  I know I'd have
> a very hard time picking out which section was what if I didn't already
> know the answer ahead of time.
>
>
>
> [1] https://postgis.net/workshops/postgis-intro/_images/de9im3.jpg
>
> On 4/15/22 15:08, Shaozhong SHI wrote:
>
> This is very interesting.
>
> However, this needs to be further detailed with a table to explain a
> variety of cases and uses.
>
> Regards,
>
> David
>
> On Fri, 15 Apr 2022 at 02:48, Paul Ramsey <pramsey at cleverelephant.ca>
> wrote:
>
>> https://postgis.net/workshops/postgis-intro/de9im.html
>>
>> > On Apr 14, 2022, at 4:35 PM, Shaozhong SHI <shishaozhong at gmail.com>
>> wrote:
>> >
>> > The use of ST_Relate appears very attractive.  However, there appears
>> not yet a table detailing DE_9IE patterns and types of topological
>> relations.
>> >
>> > There also appears that not much literature on the use of it for data
>> quality assurance or things like deriving quality data from raw data.
>> >
>> > Can anyone enlighten me?
>> >
>> > Regards,
>> >
>> > David
>> > _______________________________________________
>> > postgis-users mailing list
>> > postgis-users at lists.osgeo.org
>> > https://lists.osgeo.org/mailman/listinfo/postgis-users
>>
>> _______________________________________________
>> postgis-users mailing list
>> postgis-users at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/postgis-users
>>
>
> _______________________________________________
> postgis-users mailing listpostgis-users at lists.osgeo.orghttps://lists.osgeo.org/mailman/listinfo/postgis-users
>
>
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/postgis-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20220418/38e4f882/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 87LxNc196ZT34DAO.png
Type: image/png
Size: 112894 bytes
Desc: not available
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20220418/38e4f882/attachment.png>