topic Re: nearest feature to a given point in Python Questions

nearest feature to a given point

Faris_TawfiqAbdelFattah — Thu, 02 Mar 2017 12:10:35 GMT

hi all,

Am looking for a python code to find the nearest feature (street layer) for any given point (x,y) on the map.

i need to return the feature id only.

#python #arcpy

Re: nearest feature to a given point

JimCousins — Thu, 02 Mar 2017 17:23:29 GMT

ArcInfo level license: use the Near tool.

Basic level license: perhaps start with a spatial join and go from there?

Best Regards,

Jim

Re: nearest feature to a given point

Faris_TawfiqAbdelFattah — Sat, 04 Mar 2017 09:11:24 GMT

Thanks a lot Jim.

the near tool will add fields to the layer used, am looking for another way which will return only the FIDs so i can loop through them and read information.

something like featurecursor interface in arcobjects.

thanks again for your replay.

Re: nearest feature to a given point

JoshuaBixby — Sat, 04 Mar 2017 17:12:03 GMT

Generate Near Table. Put the table in-memory and then use a cursor to loop through it looking for FIDs. The original table stays intact.

Re: nearest feature to a given point

Faris_TawfiqAbdelFattah — Sun, 05 Mar 2017 07:07:24 GMT

Thanks Joshua ,

i tried the tool, it does not take a point object (it needs a feature layer as an input). i need to let the user input the point coordinates in order to search the nearest feature and return its information.

unfortunately the two methods (near_analysis, generate near table) are not helping.

thanks

Re: nearest feature to a given point

DanPatterson_Retired — Sun, 05 Mar 2017 09:25:01 GMT

You can use a point they created. It sounds like you need to code the ability for a person to enter a point first then run one of those two analysis options.

Re: nearest feature to a given point

JoshuaBixby — Sun, 05 Mar 2017 15:00:38 GMT

As is the case with most geoprocessing tools, the in_features can be ArcPy Geometry objects in addition to feature layers. In your case, create a PointGeometry object for the coordinates you want, and then pass that point geometry as the in_features to the Generate Near Table tool.

Re: nearest feature to a given point

Faris_TawfiqAbdelFattah — Mon, 27 Mar 2017 07:07:28 GMT

Thank you Joshua , Dan and JIM

Finally i created the tool which without your suggestions i couldn't make it.

def Closest_RD_XY( X, Y, Near_FC , Meters 😞
try:

SR = arcpy.SpatialReference(4326)# WGS84 GCS
pntFC = arcpy.CreateFeatureclass_management("in_memory", "Acc_FC", "POINT", spatial_reference = SR)

# Just to check if layer created or not
if pntFC is None:
print "FeaClass 'Acc_FC' is not created"

   #-------------------------------------------
   In_curs = arcpy.da.InsertCursor( pntFC , ["SHAPE@XY"])
   INValue = In_curs.insertRow([(X, Y)])
   if INValue < 1 : print "point is not inserted"
   del In_curs

   # use the near tool in arcpy
   arcpy.Near_analysis(pntFC, Near_FC , str(Meters)+ " Meters", "LOCATION","ANGLE","GEODESIC")
   S_curs = arcpy.da.SearchCursor(pntFC, "*")
   RD_ID = S_curs.next()

   # return all information of the nearest feature
   SN_curs =arcpy.da.SearchCursor(Near_FC, "*", "OBJECTID = " + str(RD_ID[2]))
   NFeature = SN_curs.next()

   #delete in memory point layer
   arcpy.Delete_management (pntFC)
   return NFeature

except Exception as e:
return "Error No Road found within 100 Meters 'Error ': " + e.message