I have written a Python GeoProcessing task for running Cost Distance and Cost Path analysis. It runs sometimes and errors other times. This is the error that it normally returns when trying to run the arcpy.sa.CostDistance() method:
ERROR 999999: Error executing function.
The table was not found. [VAT_CostDis_src_1]
The table name is invalid.
No spatial reference exists.
The operation was attempted on an empty geometry.
ERROR 010029: Unable to create the raster E:\WorkingFiles\ProjectFolders\LRT\Development\Test10\Scratch_hvil26w5.gdb\45a2i1023_b. Cost Distance mapping Failed
ERROR 010067: Error in executing grid expression.
Both the source point raster and the cost raster have a VAT. I rebuild the VATs in the script prior to running the tool.
Any idea why this is occurring? It is weird that it is intermittent. It seems like it will run once and then not a second time, if that is a clue.
Thanks, Dave
Here is the meat of the script:
Crashes on the CostDistance method.
Quote:
ERROR 999999: Error executing function.
The table was not found. [VAT_CostDis_src_1]
The table name is invalid.
No spatial reference exists.
The operation was attempted on an empty geometry.
ERROR 010029: Unable to create the raster E:\WorkingFiles\ProjectFolders\LRT\Development\Test10\Scratch_hvil26w5.gdb\45a2i1023_b. Cost Distance mapping Failed
ERROR 010067: Error in executing grid expression.
Any idea why this is occurring? It is weird that it is intermittent. It seems like it will run once and then not a second time, if that is a clue.
Thanks, Dave
Here is the meat of the script:
Code:
#get the Source Points feature class
pntfc = gdb + "\\WAYPOINTS"
if not arcpy.Exists(pntfc):
raise Exception("Did not find the SOURCE Points feature class")
#Get the source grid
suitgrid = getSuitGrid(gdb, suitid)
if suitgrid["code"] == "None":
raise Exception("Did not find the Suitability Grid name")
#get the Suitability grid
srcsg = gdb + "\\" + suitgrid["code"]
if not arcpy.Exists(srcsg):
raise Exception("Did not find the Suitability grid")
#query the source Ids and make a layer
arcpy.AddMessage("Query Waypoints")
srcqry = "PNTID = " + str(srcid)
pntlaynm = "waypnts"
if arcpy.Exists(pntlaynm):
arcpy.Delete_management(pntlaynm)
arcpy.MakeFeatureLayer_management(pntfc, pntlaynm)
arcpy.SelectLayerByAttribute_management(pntlaynm, "NEW_SELECTION", srcqry)
costCnt = int(arcpy.GetCount_management(pntlaynm).getOutput(0))
if costCnt < 1:
raise Exception("No Source points found for those Ids")
#copy to scratch
srcfc = scrws + "\\src_pnt"
arcpy.CopyFeatures_management(pntlaynm, srcfc)
arcpy.AddField_management(srcfc, "VAL", "LONG")
arcpy.CalculateField_management(srcfc, "VAL", 0, "PYTHON_9.3")
#select and copy out destination
destqry = "PNTID = " + str(destid)
arcpy.SelectLayerByAttribute_management(pntlaynm, "NEW_SELECTION", destqry)
#copy to scratch
destfc = scrws + "\\dest_pnt"
arcpy.CopyFeatures_management(pntlaynm, destfc)
arcpy.AddField_management(destfc, "VAL", "LONG")
arcpy.CalculateField_management(destfc, "VAL", 0, "PYTHON_9.3")
writeToLog("Copied Destination Point: " + destfc)
#set the raster geoprocessing environment
outsr = arcpy.SpatialReference(suitgrid["srfc"])
env.outputCoordinateSystem = outsr
env.extent = arcpy.Extent(suitgrid["xmin"], suitgrid["ymin"], suitgrid["xmax"], suitgrid["ymax"])
env.cellSize = suitgrid["res"]
#Convert src point to raster
srcras = scrws + "\\src_ras"
arcpy.PointToRaster_conversion(srcfc, "VAL", srcras, "", "", suitgrid["res"])
arcpy.BuildRasterAttributeTable_management(srcras, "NONE")
#Convert dest point to raster
destras = scrws + "\\dest_ras"
arcpy.PointToRaster_conversion(destfc, "VAL", destras, "", "", suitgrid["res"])
arcpy.BuildRasterAttributeTable_management(destras, "NONE")
#Delete the point layer if it still exists
if arcpy.Exists(pntlaynm):
arcpy.Delete_management(pntlaynm)
#Rebuild the raster Vat on the suitability grid
#arcpy.AddMessage("Rebuild the Suitability Grid VAT")
#arcpy.BuildRasterAttributeTable_management(srcsg, "NONE")
#run the Cost Distance tool for the source point
arcpy.AddMessage("Run Cost Distance")
srcsgdist = scrws + "\\" + costgrd["COSTCODE"] + "_c"
srcsgback = scrws + "\\" + costgrd["COSTCODE"] + "_b"
outcost = CostDistance(srcras, srcsg, "", srcsgback)
outcost.save(srcsgdist)