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Esteban A. Maringolo

PostGIS in Pharo

Is there anybody using PostGIS in Pharo?

Regards!

Esteban A. Maringolo

hernanmd

Re: PostGIS in Pharo

Can you comment what are you trying to do?

Hernán

2015-01-28 13:10 GMT-03:00 Esteban A. Maringolo <[hidden email]>:

Is there anybody using PostGIS in Pharo?

Regards!

Esteban A. Maringolo

Esteban A. Maringolo

Re: PostGIS in Pharo

Sure,

I'll collect georeferenced data in a mobile app, which I'll later have to group each one according to whether they fall inside a certain polygon (geopolitcal boundaries, like city, district, province, etc.).

I could also geocode the coordinate and store all that data (city, district, province, etc.), and then just group by each of these. And then I'll have to plot that data on a choropleth map.

But I'm asking to know if somebody has somehow mapped smalltalk geometry objects to the typical geometry object of PostGIS. Something like PGPoint, PGPolygon, that can "translate" themselves from/to string literals.

I'm trying to avoid writing everything by hand in SQL.

Regards!

pd: I'm also considering using something like CartoDB for this task, which is a few levels of abstraction higher.

Esteban A. Maringolo

2015-01-28 16:07 GMT-03:00 Hernán Morales Durand <[hidden email]>:

Can you comment what are you trying to do?

Hernán

2015-01-28 13:10 GMT-03:00 Esteban A. Maringolo <[hidden email]>:
Is there anybody using PostGIS in Pharo?

Regards!

Esteban A. Maringolo

hernanmd

Re: PostGIS in Pharo

2015-01-28 16:18 GMT-03:00 Esteban A. Maringolo <[hidden email]>:

Sure,

I'll collect georeferenced data in a mobile app, which I'll later have to group each one according to whether they fall inside a certain polygon (geopolitcal boundaries, like city, district, province, etc.).
I could also geocode the coordinate and store all that data (city, district, province, etc.), and then just group by each of these. And then I'll have to plot that data on a choropleth map.

But I'm asking to know if somebody has somehow mapped smalltalk geometry objects to the typical geometry object of PostGIS. Something like PGPoint, PGPolygon, that can "translate" themselves from/to string literals.

I don't know about PostGIS, but if you need boundary datasets there is GADM or GeoNames which may cover your needs.
Recently I did a ST script to read from GADM using a dBase package. And you could query throug SPARQL too.

Hernán

stepharo

Re: PostGIS in Pharo

In reply to this post by Esteban A. Maringolo

Why would you have to do that in SQL?
Why you cannot import PGPoint and PGPolygon in Pharo?

Sure,

I'll collect georeferenced data in a mobile app, which I'll later have to group each one according to whether they fall inside a certain polygon (geopolitcal boundaries, like city, district, province, etc.).

I could also geocode the coordinate and store all that data (city, district, province, etc.), and then just group by each of these. And then I'll have to plot that data on a choropleth map.

But I'm asking to know if somebody has somehow mapped smalltalk geometry objects to the typical geometry object of PostGIS. Something like PGPoint, PGPolygon, that can "translate" themselves from/to string literals.

I'm trying to avoid writing everything by hand in SQL.

Regards!

pd: I'm also considering using something like CartoDB for this task, which is a few levels of abstraction higher.

Esteban A. Maringolo

2015-01-28 16:07 GMT-03:00 Hernán Morales Durand <[hidden email]>:

Can you comment what are you trying to do?

Hernán

2015-01-28 13:10 GMT-03:00 Esteban A. Maringolo <[hidden email]>:

Is there anybody using PostGIS in Pharo?

Regards!

Esteban A. Maringolo

Esteban A. Maringolo

Re: PostGIS in Pharo

In reply to this post by hernanmd

2015-01-28 17:01 GMT-03:00 Hernán Morales Durand <[hidden email]>:

2015-01-28 16:18 GMT-03:00 Esteban A. Maringolo <[hidden email]>:

I don't know about PostGIS, but if you need boundary datasets there is GADM or GeoNames which may cover your needs.
Recently I did a ST script to read from GADM using a dBase package. And you could query throug SPARQL too.

GADM is EXACTLY the database I was looking for.

I didn't understand the dbase package part, but I was able to download a KMZ file with all needed.

Thank you SO MUCH!

Esteban A. Maringolo

Re: PostGIS in Pharo

In reply to this post by stepharo

2015-01-28 17:17 GMT-03:00 stepharo <[hidden email]>:

Why would you have to do that in SQL?

PostGIS is a little more than SQL, SQL enables you to query it, but it provides you with a lot of GIS functionality.

I woudn't load a million rows into Pharo memory to search nearby locations to a coordinate, or group results based on whether they are inside of a certain boundary.

Why you cannot import PGPoint and PGPolygon in Pharo?

Right now there is no PGPoint nor any of the PostGIS geometry objects in Pharo. Mainly because of that.

If its worth, I might end up creating those abstractions. So I can also create the proper "converter" to map back and forth using GLORP.

Regards,

Esteban A. Maringolo

Arturo Zambrano

Re: PostGIS in Pharo

In reply to this post by Esteban A. Maringolo

Hi Esteban,All

I'm facing almost the same requirement. I have coordinates and I need to determine to which location they belong to (for example to which province).

I checked that GADM and level 1 file should suffice. Now, how to did you use this information in Pharo? Which library/framework should I used to access and query the information contained in the KML?.

Thanks in advance.

art

On Wed, Jan 28, 2015 at 5:22 PM, Esteban A. Maringolo <[hidden email]> wrote:

2015-01-28 17:01 GMT-03:00 Hernán Morales Durand <[hidden email]>:

2015-01-28 16:18 GMT-03:00 Esteban A. Maringolo <[hidden email]>:

I don't know about PostGIS, but if you need boundary datasets there is GADM or GeoNames which may cover your needs.
Recently I did a ST script to read from GADM using a dBase package. And you could query throug SPARQL too.

GADM is EXACTLY the database I was looking for.

I didn't understand the dbase package part, but I was able to download a KMZ file with all needed.

Thank you SO MUCH!

Esteban A. Maringolo