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Need to convert polygons to points in shp files

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#1
on point

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Ive been looking all over for a GIS editor that can convert an ESRI shape file with polygon data in it to an ESRI shape file with point data in it without losing any attribute info and without doing it one polygon at a time. It seems this would be easy to do, replace a polygon with a point at the centroid of the polygon.

But honestly Im inches away from just eating a bullet so I dont have to think about it anymore... someone please tell me there is a simple solution to this.

#2
Martin Gamache

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Nathan,

This type of geoprocessing is the bread and butter of GIS software, I know how to do this conversion globally in both ARCGIS and Manifold, do you have access to either. If not, contact me off-list and we can figure something out...

mg

#3
Hans van der Maarel

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Nathan,

I personally prefer to use FME (see here) for this kind of work. If you send me the file I can probably whip something up in about 5 minutes.
Hans van der Maarel - Cartotalk Editor
Red Geographics
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#4
on point

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cool, I'll check that out, thanks

#5
JimBlakeslee

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I don't know about ESRI but in MapInfo Pro you just add two columns, one for lat one for long, then "update" each column with CentroidX and Centroid Y. Then save it out as just the data file, reimport it, and "create points" based on the new column. This keeps the attribute table completely intact.

I bet ESRI would be similar.

#6
on point

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nice, thanks

#7
frax

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just for the record, this is extremely simple using ArcInfo Coverages, just build point topology on the polygon coverage and use that.
Hugo Ahlenius
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#8
CrazeUK

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Hi Guys, i know this is resurecting a very old thread.

I use ArcMap, and need to convert a Polygon Shapefile to Points.
I also have access to FME, but i havenever used it.

Does anyone know if there is a guide out there that i can use to learn to do this.

Thanks
Saff

#9
GIS xtra

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you can use ETgeowizards in Arcgis (can be done with demo version)

#10
Hans van der Maarel

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I use ArcMap, and need to convert a Polygon Shapefile to Points.
I also have access to FME, but i havenever used it.


You can set up a workbench in FME to take care of this. You can use a Chopper transformer, with maximum vertices set to "1" to turn polygons into their constituent points. If your polygons are touching, you will end up with duplicate points though. Those can be filtered out, but that's a bit more complex to explain (I have to leave here in a few minutes). I'd be happy to post a more detailed description with screenshots tomorrow.
Hans van der Maarel - Cartotalk Editor
Red Geographics
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#11
Laura Miles

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Use "Feature to Point" in ArcToolbox if you want centroids; "Feature Vertices to Points" if you want vertex points.

#12
dr.vita01

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Hi everyone,
I'm relatively new in GIS, and I have similar problem. I also want to convert polygon to point files but I have more then one polygon files overlapping so the centroids are overlapping to. How to avoid that overlapping?

#13
French cartographer

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Hi everyone,
I'm relatively new in GIS, and I have similar problem. I also want to convert polygon to point files but I have more then one polygon files overlapping so the centroids are overlapping to. How to avoid that overlapping?


Hello,
You can use a QGIS extension to do that.

#14
evelyngis

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Hi, dr.vita01,

I can help you with your overlapping problem.

Is it possible to send me your data file? I can fix it soon....

Or you can add my Gtalk: bnu.liping@gmail.com




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