topic Re: Contour with Barriers vs. Contour in ArcGIS Spatial Analyst Questions

Contour with Barriers vs. Contour

WesKing — Thu, 24 Jun 2010 19:13:35 GMT

9.3.1 sp1 Spatial Analyst extension
I've noticed that working on the same DEM, the shapefile output for 'Contour' and 'Contour with Barriers' is quite in the amount of contours created. On the DEMs I'm working with, 'Contour with Barriers' seems to never create contour segments that are less than 27 meters in length while 'Contour' will create contour segments that are extremely small in length (hundredths or thousandths of a meter, maybe more...I can't recall).

Can anyone explain why this works this way, including the determination of minimum segment length.

Thanks in advance,
Wes

Re: Contour with Barriers vs. Contour

SteveLynch — Fri, 25 Jun 2010 12:33:44 GMT

Wes

Totally different algorithms are used.

Steve Lynch
ESRI

Re: Contour with Barriers vs. Contour

WesKing — Fri, 25 Jun 2010 13:48:52 GMT

Thanks Steve. I figured as much, but I'm curious if Contour with Barriers has some kind of determination on where to draw the line on minimum segment lengths to include or exclude. For the DEMs I'm using Contour with Barriers is great because the memory allocation error never happens like it does in the Contour tool. But I also don't want to lose possibly valuable data.

Thanks,
Wes