topic Selecting polyline features with values from a raster layer in Geoprocessing Questions

Selecting polyline features with values from a raster layer

RyanBown — Fri, 15 Jul 2011 21:04:39 GMT

Hi,

I am trying to select polyline features which lie on raster cells that are above a given threshold value. The raster cells are valued from 3-9 and I want to select the polylines that lie on cells valued at 6 or higher. The only way that I can think of to do this is to decide the threshold, in my case 6, and then selected the cells above the value. Then convert the result to a vector, do a "select by location" to find all the polylines that are completely within a polygon with the value = 1However, when I try to use ArcScan to export the selection to a new layer, the Arcscan toolbar isn't active.

Can anyone help me or have a better idea on how to select the features using raster data?

Thanks,
Ryan

Re: Selecting polyline features with values from a raster layer

DanLee — Mon, 18 Jul 2011 15:51:04 GMT

You can try Raster To Polygon tool (Conversion toolbox - From Raster toolset) to get polygons with cell values.

Regards.

Re: Selecting polyline features with values from a raster layer

CliveCartwright — Mon, 28 Apr 2014 09:22:02 GMT

I am trying to select polyline features which lie on raster cells that are above a given threshold value.

What I need to do requires the same process, but other than converting to polygon the chosen threshold isolated through a 'reclass', followed by the Intersect tool, I'm no further. It all feels a little clumsy.

It is a shame there's no facility in the Intersect tool that allows you to read raster's and choose a classification threshold of some sort. It would reduce the processing stages in py script if a more efficient method exists.