topic Re: IDW when several points are falling into the same location in ArcGIS Spatial Analyst Questions

IDW when several points are falling into the same location

josesanchez1 — Tue, 13 Aug 2013 11:45:56 GMT

Hi all,

I am using IDW with thousands of points. Many of them are in the same location.

Does IDW method in ArcGIS consider them as a single location when it runs?

Should I dissolve all repeated ones into single points?

Thanks in advance,

Jose.

Re: IDW when several points are falling into the same location

DanPatterson_Retired — Tue, 13 Aug 2013 11:51:35 GMT

Remove the duplicates to be on the safe side, there is no guarantee that this is done prior to running IDW

Re: IDW when several points are falling into the same location

SteveLynch — Tue, 13 Aug 2013 14:20:41 GMT

IDW in Spatial Analyst will only use one point. However, it may be the first or last one encountered. Geostatistical Analyst on the other hand lets you control how coincident data should be handled.

A big word of caution. There are many tools available in ArcGIS to identify and manipulate coincident data. Use them to determine which points to drop. For example, you have 5 coincident points. 1 has a "good" value and the other 4 have "bad" values. You need to make sure that you're using the "good" one.

Steve

Re: IDW when several points are falling into the same location

josesanchez1 — Wed, 14 Aug 2013 20:25:53 GMT

Thanks,

I was wondering which are the methods that generate a mean value for all identical points, given a specific field.

I have found that Merge_management does not do it. Either FindIdentical_management.

Is it the dissolve one the only available tool for that?.

thanks in advance,

Jose