Negative buffer - skipped features

[JamesDuffy]

Hello,

I am using ArcMap 9.3.1 with ArcInfo license. I am trying to make a negative buffer for a large set of contiguous but non-overlapping polygons. However, out of the 108,087 polygons it skipped 429 of them and left this error message for each of the features it skipped:

WARNING 000636: Skipping feature [FID] because a negative or very small distance resulted in no geometry.

I know for sure that the polygons are big enough and will not disappear from this negative buffer; they are all a very similar size.
I got the FIDs into a column in excel and extracted just these features into another shp and tried the negative buffer again and it only worked on the first one and skipped the rest.

I am currently splitting the polygon shp and will batch buffer on each one individually and hopefully it will work. However, does anyone know why this is happening and if there's a better solution?

Thanks,

James

[MelitaKennedy]

Hello,

I am using ArcMap 9.3.1 with ArcInfo license. I am trying to make a negative buffer for a large set of contiguous but non-overlapping polygons. However, out of the 108,087 polygons it skipped 429 of them and left this error message for each of the features it skipped:


I know for sure that the polygons are big enough and will not disappear from this negative buffer; they are all a very similar size.
I got the FIDs into a column in excel and extracted just these features into another shp and tried the negative buffer again and it only worked on the first one and skipped the rest.

I am currently splitting the polygon shp and will batch buffer on each one individually and hopefully it will work. However, does anyone know why this is happening and if there's a better solution?

Thanks,

James

Hi James,

Have you tried running the Check Geometry tool? Otherwise, I don't know what the problem could be.

Melita

[KatharinaDubach]

could it be that your polygons have self-intersection resulting in tiny additional slivers or minute holes that make the buffer tool stumble?

[JamesDuffy]

Hi James,

Have you tried running the Check Geometry tool? Otherwise, I don't know what the problem could be.

Melita

Hi Melita,

Thanks for your response. There were no geometry problems. The polygon shp was actually made from the tool which makes Thiessen/voronoi polygons. The method of making them individually worked. I couldn't identify any pattern for the ones it skipped and it's so unusual that when I ran each feature as an individual shp, as opposed to being part of many polygon features within one shp, it worked fine. I might try running it on v.10 when I get the chance.

[JamesDuffy]

Hello All,

I would like to highlight this problem again, as it is causing me a lot more grief than before.  I have about 3000 polygons which won't buffer negative values from a field in the attribute table.  I have tried repairing the geometry but the buffer process still skips over all of them producing an empty output file.

E.g.

AFIUCN1234Thiessens - the original set of polygons which I buffered using the field 'NegHalfAM'
AFIUCNThieseensSkips2 - the polygons that did not have buffers created for them due to error 000636

Buffering the polygons in the AFIUCNThiessenSkips2 file results in an empty output as all of the features are skipped.

Can anyone think how to solve this problem?

Cheers,

James

[AlexandruVasile2]

Solved! I think....

In my case it was because of the Projection. I was using WGS aux. Sphere...

I used project to my local system (Stereo70 for Romania) and the problem was solved.

This issue still sucks but maybe this is of help