topic Re: ArcPy - How to create a perpendicular line to an existing line since one especific point in ArcGIS in Python Questions

ArcPy - How to create a perpendicular line to an existing line since one especific point in ArcGIS

Comisión_Estatal_de_Aguasde_Qu — Thu, 18 Aug 2016 22:33:27 GMT

Hello! I am currently generating a layer parallel to a layer of existing lines , from a point layer lines . Can someone please help me to resolve this situation ? Thank you very much.

Re: ArcPy - How to create a perpendicular line to an existing line since one especific point in ArcGIS

DanPatterson_Retired — Thu, 18 Aug 2016 23:01:13 GMT

If memory serves

Near—Help | ArcGIS for Desktop followed by

XY To Line—Help | ArcGIS for Desktop

once you have your from and to, xy coordinates

... cavaet... you have the advanced license for ArcMap

Re: ArcPy - How to create a perpendicular line to an existing line since one especific point in ArcGIS

DarrenWiens2 — Sun, 12 Dec 2021 02:47:24 GMT

This is possible with Python and Basic license, although untested for large datasets (I did run this against 1000+ points and it was fine).

First step is to dissolve all roads into a single feature, although you could loop through them with added code.

>>> points = "points_select" # points layer
... sr = arcpy.Describe(points).spatialReference # get CRS
... lines = "roads_select" # roads feature class containing single, merged feature for all roads
... out_lines = [] # output list
... line_geom = [i[0] for i in arcpy.da.SearchCursor(lines,'SHAPE@',spatial_reference=sr)] # the road feature
... with arcpy.da.SearchCursor(points,'SHAPE@') as cursor: # loop through points
... for row in cursor:
... end = line_geom[0].queryPointAndDistance(row[0])[0].centroid # get nearest point on line
... start = row[0].centroid 
... out_lines.append(arcpy.Polyline(arcpy.Array([start,end]),sr)) # connect the dots and add to line list
... arcpy.CopyFeatures_management(out_lines,r'in_memory\out_lines') # write line list to disk‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍