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I input firms' coordinates in the arcgis and want to calculate the distance of firms to the nearest polyline feature (roads). I am having a problem grasping the unit of near_dist value. All of them are in hundredth or thousandth like .00475. Most likely the value is expressed in the coordinate system. But I would like them to be shown as in the metric system.

ArcGis has a help file that mentions you need to change the method parameter from planar to geodesic and that conversion will give you an near_dist value in meters.

But I am really having trouble to find the method parameter setting. Can anyone walk me through how to find it. I am using ArcMap 10.2 and windows 32-bit.

enter image description here

output: enter image description here

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  • Confirm that your layer is in WGS84, if it is, then project the data into a coordinate system where the units of measure are in metres.
    – Hornbydd
    Jul 17, 2016 at 18:30
  • Thanks for the comment. Ok, I changed both the point layer and the line layer to WGS_1984_UTM_Zone_20N and the linear units are meters. But my near_dist value is still so small. Do I not do something to get it right?
    – Tobias Zihao Wang
    Jul 18, 2016 at 0:06

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You should make sure that both of your datasets are in the same coordinate system, and make sure that it is a coordinate system whose linear unit is Metres. The output measurement should then be in metres.

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  • Thank you for the answer. I put both my datasets in WGS_1984_UTM_Zone_20N and the unit of measure is meters. But I still can't get a sensible near_dist value. Could you tell me where I did wrong ?
    – Tobias Zihao Wang
    Jul 18, 2016 at 0:10
  • Looking at the image the nearest XY coordinate would suggest the data is still in decimal degrees. You did project the data using the project tool rather than use the define projection tool?
    – Hornbydd
    Jul 18, 2016 at 9:18
  • @Hornbydd Thanks for spotting my misstep. Instead of using the define projection tool, I use the project tool this time to project both layers into WGS_1984_UTM_Zone_12N. I am putting the results as images above. I don't think the result is satisfactory. NearXY coordinate is messed up. Near_dist value is changed but is still too small.
    – Tobias Zihao Wang
    Jul 18, 2016 at 16:10
  • A post said "WGS84 and NAD83 both refer to datums not projections. If you want to project your data, I would be inclined to use either a UTM zone, or a US-wide projection if you're dealing with large areas." I tried changing the prj coordinate system to USA_Contiguous_Albers_Equal_Area_Conic_USGS_version. It's still not working.
    – Tobias Zihao Wang
    Jul 18, 2016 at 18:09
  • Ok. I just figured it out. Please refer to this post and see mkennedy and Chris W's comments. They are very helpful. gis.stackexchange.com/questions/154652/…
    – Tobias Zihao Wang
    Jul 19, 2016 at 5:56

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