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I have a set of points along a river-channel which contain attributes to of the right and left riparian classification respectively. These points almost follow the channel center-line, and have been separated so that I have a point-shapefile with the right's bank classification and another shapefile for the left classification (let's call either shapefile as SHAPEF_CLASS). In the graphic below, the shapefile with the classification (desired attributes) is represented with the bold black dots.

enter image description here

The colored dots represent another shapefile that contains bathymetric data (SHAPEF_BATHY). I would like to assign the river bank classification attribute from SHAPEF_CLASS to SHAPEF_BATHY. I tried converting the SHAPEF_CLASS to a raster (see below) with the intention to use the Identity tool to extract the classification values. However, the resulting raster does not cover the extent of the river channel so most of the bathymetry point are not covered.

River classification points to raster

I am using ARCMAP 9.3. I used the default cell size (0.000048), but if I increase the cell size I end up loosing some of the classes from the SHAPEF_CLASS. I thought about converting the SHAPEF_CLASS from point to polyline, and increasing the width of the line so it would cover the entire width of the river channel and then extract the classification. I also have a polygon of the river channel. Not if that would be useful for what I want to do though.

Any suggestions would be welcomed.

  • Have you tried doing an intersect with a XY tolerance suitable to capture the attributes you need? – Aaron Jan 7 '14 at 19:33
  • yeah as Aaron suggests. actually the spatial join may be the next best method. comment Barbarossa's answer if it doesn't work. I will post more info on spatial join. – Brad Nesom Jan 7 '14 at 21:25
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If I understand your question, you would like to get attributes from the the black dots into the color dots. What if you used the near tool to get the OID of the nearest black dot to each color dot? Then do a join based on this OID to get whatever attributes you like from the black dots into the color dots.

Try the generate near table tool.
Calculates distances and other proximity information between features in one or more feature class or layer. Unlike the Near tool, which modifies the input, Generate Near Table writes results to a new stand-alone table and supports finding more than one near feature.

  • Thanks Babarossa, seems like it will do the trick. Wasn't aware of the near tool though...thanks again – user2507608 Jan 7 '14 at 18:01
  • Just tried, but realized that the near tool only gives the nearest point. This won't work as multiple color points could be associated with one black dot, and as such, there will be many colored points that are not accounted for. – user2507608 Jan 7 '14 at 18:42
  • Is the relationship one-to-one? It looks as if there are way more color points than black. – Barbarossa Jan 7 '14 at 19:12
  • No the relationship is one to many. I was trying to get a "buffer" around a set of points that belonged to one class, and use that to add the values to the colored points – user2507608 Jan 7 '14 at 20:19
  • @ Brad, Thanks. I will try it immediately so see how it works. – user2507608 Jan 7 '14 at 20:20

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