def runTool(outDir, outGDB, inSQLDbase, inNetworkDataset, imp, BufferSize,
restrictions, TrimSettings):
try:
# ----- Set up the run -----
try:
BBB_SharedFunctions.CheckArcVersion(min_version_pro="1.2")
BBB_SharedFunctions.CheckArcInfoLicense()
BBB_SharedFunctions.CheckOutNALicense()
BBB_SharedFunctions.CheckWorkspace()
# It's okay to overwrite in-memory stuff.
OverwriteOutput = arcpy.env.overwriteOutput # Get the orignal value so we can reset it.
arcpy.env.overwriteOutput = True
# Append .gdb to geodatabase name.
if not outGDB.lower().endswith(".gdb"):
outGDB += ".gdb"
outGDBwPath = os.path.join(outDir, outGDB)
# Create a file geodatabase for the results.
arcpy.management.CreateFileGDB(outDir, outGDB)
# Make a copy of the input SQL file in the Step 1 output so we can modify it.
SQLDbase = os.path.join(outGDBwPath, "Step1_GTFS.sql")
copyfile(inSQLDbase, SQLDbase)
# Connect to or create the SQL file.
conn = sqlite3.connect(SQLDbase)
c = BBB_SharedFunctions.c = conn.cursor()
impedanceAttribute = BBB_SharedFunctions.CleanUpImpedance(imp)
TrimPolys, TrimPolysValue = BBB_SharedFunctions.CleanUpTrimSettings(
TrimSettings)
except:
arcpy.AddError("Error setting up run.")
raise
#----- Make a feature class of GTFS stops that we can use for buffers -----
try:
# Create a feature class of transit stops
arcpy.AddMessage("Creating a feature class of GTFS stops...")
StopsLayer, StopIDList = BBB_SharedFunctions.MakeStopsFeatureClass(
os.path.join(outGDBwPath, "Step1_Stops"))
except:
arcpy.AddError("Error creating a feature class of GTFS stops.")
raise
#----- Create Service Areas around all stops in the system -----
try:
arcpy.AddMessage("Creating service areas around stops...")
arcpy.AddMessage(
"(This step will take a while for large networks.)")
polygons = BBB_SharedFunctions.MakeServiceAreasAroundStops(
StopsLayer, inNetworkDataset, impedanceAttribute, BufferSize,
restrictions, TrimPolys, TrimPolysValue)
except:
arcpy.AddError("Error creating service areas around stops.")
raise
#----- Post-process the polygons to prepare for Step 2 -----
try:
arcpy.AddMessage("Reformatting polygons for further analysis...")
arcpy.AddMessage(
"(This step will take a while for large networks.)")
# ----- Flatten the overlapping service area polygons -----
# Use World Cylindrical Equal Area (WKID 54034) to ensure proper use of cluster tolerance in meters
arcpy.env.outputCoordinateSystem = BBB_SharedFunctions.WorldCylindrical
# Flatten the overlapping polygons. This will ultimately be our output.
# Dummy points to use in FeatureToPolygon to get rid of unnecessary fields.
dummypoints = arcpy.management.CreateFeatureclass(
"in_memory", "DummyPoints", "POINT")
# The flattened polygons will be our ultimate output in the end (final
# output of step 2).
FlatPolys = os.path.join(outGDBwPath, "Step1_FlatPolys")
# FeatureToPolygon flattens overalpping polys.
# Set a large cluster tolerance to eliminate small sliver polygons and to
# keep the output file size down. Boundaries may move up to the distance
# specified in the cluster tolerance, but some amount of movement is
# acceptable, as service area polygons are inexact anyway.
# The large cluster tolerance may cause some geometry issues with the output
# later, but this is the best solution I've found so far that doesn't eat
# up too much analysis time and memory
clusTol = "5 meters"
arcpy.management.FeatureToPolygon(polygons, FlatPolys, clusTol, "",
dummypoints)
arcpy.management.Delete(dummypoints)
# Add a field to the output file for number of trips and num trips / hour.
# Also create a polygon id field so we can keep track of them.
arcpy.management.AddField(FlatPolys, "PolyID", "LONG")
arcpy.management.AddField(FlatPolys, "NumTrips", "LONG")
arcpy.management.AddField(FlatPolys, "NumTripsPerHr", "DOUBLE")
arcpy.management.AddField(FlatPolys, "NumStopsInRange", "LONG")
arcpy.management.AddField(FlatPolys, "MaxWaitTime", "DOUBLE")
# ----- Create stacked points, one for each original SA polygon -----
# Create points for use in the Identity tool (one point per poly)
FlattenedPoints = os.path.join(outGDBwPath,
"Step1_FlattenedPoints")
arcpy.management.FeatureToPoint(FlatPolys, FlattenedPoints,
"INSIDE")
# Use Identity to stack points and keep the stop_ids from the original SAs.
# Results in a points layer with fields ORIG_FID for the IDs of the
# flattened polygons and a stop_id column with the stop ids.
# Points are stacked, and each has only one stop_id.
StackedPoints = os.path.join(outGDBwPath, "Step1_StackedPoints")
arcpy.analysis.Identity(FlattenedPoints, polygons, StackedPoints)
arcpy.management.Delete(FlattenedPoints)
# ----- Read the Stacked Points into an SQL table -----
# Create a SQL table associating the Polygon FID with the stop_ids that serve it.
c.execute("DROP TABLE IF EXISTS StackedPoints;")
schema = "Polygon_FID LONG, stop_id TEXT"
create_stmt = "CREATE TABLE StackedPoints (%s);" % schema
c.execute(create_stmt)
# Add data to the table. Track Polygon IDs with no associated stop_ids so we can delete them.
FIDsToDelete = []
AddToStackedPts = []
with arcpy.da.SearchCursor(
StackedPoints, ["ORIG_FID", "stop_id"]) as StackedPtCursor:
for row in StackedPtCursor:
if not row[1]:
FIDsToDelete.append(row[0])
else:
AddToStackedPts.append((
row[0],
row[1],
))
# Add the OD items to the SQL table
c.executemany(
'''INSERT INTO StackedPoints \
(Polygon_FID, stop_id) \
VALUES (?, ?);''', AddToStackedPts)
conn.commit()
arcpy.management.Delete(StackedPoints)
FIDsToDelete = set(FIDsToDelete)
# ----- Delete polygons not associated with any stop_ids -----
# These were generated by the FeatureToPolygon tool in areas completely
# surrounded by other polygons and aren't associated with any stops.
# Make feature layer containing only the polygons we want to delete.
desc2 = arcpy.Describe(FlatPolys)
OutputOIDName = desc2.OIDFieldName
# Anything with 0 area will just cause problems later.
WhereClause = '"Shape_Area" = 0'
if FIDsToDelete:
WhereClause += ' OR "' + OutputOIDName + '" IN ('
for FID in FIDsToDelete:
WhereClause += str(FID) + ", "
WhereClause = WhereClause[:-2] + ")"
arcpy.management.MakeFeatureLayer(FlatPolys, "FlatPolysLayer",
WhereClause)
# Delete the polygons that don't correspond to any stop_ids.
arcpy.management.DeleteFeatures("FlatPolysLayer")
# ----- Populate the PolyID field -----
# Set PolyID equal to the OID.
expression = "!" + OutputOIDName + "!"
arcpy.management.CalculateField(FlatPolys, "PolyID", expression,
"PYTHON")
except:
arcpy.AddError("Error post-processing polygons")
raise
arcpy.AddMessage("Done!")
arcpy.AddMessage("Files written to output geodatabase " + outGDBwPath +
":")
arcpy.AddMessage("- Step1_Stops")
arcpy.AddMessage("- Step1_FlatPolys")
arcpy.AddMessage("- Step1_GTFS.sql")
# Tell the tool that this is output. This will add the output to the map.
arcpy.SetParameterAsText(8, os.path.join(outGDBwPath, "Step1_Stops"))
arcpy.SetParameterAsText(9, os.path.join(outGDBwPath,
"Step1_FlatPolys"))
arcpy.SetParameterAsText(10, os.path.join(outGDBwPath,
"Step1_GTFS.sql"))
except BBB_SharedFunctions.CustomError:
arcpy.AddError("Failed to create BetterBusBuffers polygons.")
pass
except:
arcpy.AddError("Failed to create BetterBusBuffers polygons.")
raise
