Intersection of arcpy polyline and polygon

ChroAhmed — Thu, 11 Dec 2014 13:37:00 GMT

Hi everyone,

I'm trying to find intersection of two polylines with a set of polygons to determine the segment of each polyline that intersects with the polygons.

below is my sample code, I want to get the length of the polyline's segments that intersecte with the polygons but I continuously get one of the following error messages:

1-Eceptions.TypeError:Invalid geometry type for method- : I get this error when I use (GEODESIC,PLANAR, GREAT_ELLIPTIC)as a type measurement in "getLength"method.

2- Access violation at address 5C5B11E8 in module 'GeometryXLib.dll'. Read of address 00000000: I get this error when I use (PRESERVE_SHAPE) as a type measurment in "getLength"method.

I don't Know How to solve it. Any help and suggestion are greatly appreciated.

The Code is :

import arcpy

path="E:\Code_Python\Data_trial.gdb"

arcpy.env.workspace=path

infc="CandidateStations_clipped"

fc="PopulationDensity_poly_del"

OBJ_field="OBJECTID"

#--------------------------------------------------------------------------

def get_station_shape(station_id):

with arcpy.da.SearchCursor(infc,"shape@",'%s = %s'%(OBJ_field,station_id)) as cursor:

t1=cursor.next()[0].lastPoint

return t1

#------------------------------------------------------------------------------

def get_population_shape(pop_stns):

for i in range (len(pop_stns)):

pop_list.append(get_station_shape(pop_stns))

return pop_list

#-----------------------------------------------------------------------------

def determine_line_length(pop_list_line):

pop_line=arcpy.Polyline(arcpy.Array([get_population_shape(pop_list_line)]))

return pop_line

#------------------------------------------------------------------------

# Enter for loop for each feature

def get_polygon_shape(fc):

pd_poly=[]

for row in arcpy.da.SearchCursor(fc, ["OBJECTID", "SHAPE@"]):

# Print the current multipoint's ID

print("Feature {0}:".format(row[0]))

partnum = 0

# Step through each part of the feature

for part in row[1]:

# Print the part number

print("Part {0}:".format(partnum))

# Step through each vertex in the feature

for pnt in part:

poly=[]

if pnt:

poly.append(pnt)

# Print x,y coordinates of current point

print("{0}, {1}".format(pnt.X, pnt.Y))

else:

# If pnt is None, this represents an interior ring

print("Interior Ring:")

tmp_poly=arcpy.Polygon(arcpy.Array(poly))

pd_poly.append(tmp_poly)

print tmp_poly

partnum += 1

print pd_poly

return(tmp_poly)

#---------------------------------------------------------------------------

pop_list_line=[[2,9],[1,7]]

for i in range(len(pop_list_line)):

pop_list=[]

pop_line=determine_line_length(pop_list_line)

intersect=pop_line.intersect((get_polygon_shape(fc)),2)

print intersect

pop_list.append(intersect.getLength("GEODESIC"))

print "pop_list=",pop_list

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Intersection of arcpy polyline and polygon