Round 2 in which ArcGIS throws in the towel. (Please note: This post is about clipping in ArcGIS version 10.0. The functionality has been improved, and problems mentioned have been fixed in later versions of ArcGIS) This is a follow-up to my previous post where I matched up ArcGIS and QGIS in a clipping contest. One of the commenters on that post expressed some concern that there might be “…something else going on…” with my test, and I agreed. It was unfathomable to me that an ESRI product could be out-done by such a wide margin. Knowing that ArcGIS often…
Tag: ArcGIS
ArcGIS–QGIS Faceoff
Is QGIS a viable alternative to ArcGIS? (Please note: This post is about clipping in ArcGIS version 10.0. The functionality has been improved, and problems mentioned have been fixed in later versions of ArcGIS) I’ve never enjoyed working with contours. They seem to bog down my system more than any other layer type I work with. However, most of my clients are so used to looking at USGS Topo maps they expect to see them on at least one of the maps I produce for them. I recently worked on a project covering a five-town area in the Catskill Mountain…
Find duplicate field values in ArcGIS using Python
As ESRI is making it’s move away from VB Script and towards Python, I’m also slowly updating my stash of code snippets along the way. One of those little pieces of code I use quite often is one that identifies duplicate field names in a layer’s attribute table. I find this particularly helpful when I’m cleaning up tax parcel data, looking for duplicate parcel-ID numbers or SBL strings. Since I’ve been working a lot with parcel data lately, I figured it was time to move this code over to Python, too. So, here it is in step-by-step fashion… 1 –…
Generating Vertical Buffers
One of the more popular analyses I’m asked to perform for my clients is a viewshed analysis. Beyond simply identifying what areas of a town are visible from roads or other public viewpoints, I’m often asked to help identify, and sometimes rank, areas that are most worthy of protection. One way to help a town identify and evaluate these high priority vistas, is to identify prominent ridgelines and the areas around them that are susceptible to inappropriate development. One way to mitigate the impact of development on highly visible ridgelines is to make sure new buildings do not break the…