Latest Contributions by ChrisMathers

I used to do a method that used a spatial join but after upgrading to 10 it started to fail repeatedly without returning any errors. It was as if while loading the data into the parcels a sys.exit() signal was sent. The whole shell restarted instead of a normal crash regardless of what error catching I tried to include. I think it may save time to loop once through the parcels for each 'i' instead of the other way around. Im testing that now. I may consider the dictionaries as an option if this doesnt work. The reason I am using networked data is that it is on an SDE and I would rather not have to have the code reconcile the FGDB with the SDE at the start of each run though. ... View more

Well you can try reading the geometry of the line to get the coords of the vertexs and use those to find the angle of the line. Then a point object can be created along that line wherever you would like and use that as an input for arcpy.SplitLineAtPoint_management(). ... View more

Well the biggest problem I was having was that I assumed it was more complicated than it is. To get the geometry object for a row you only have to set a variable equal to the value of the shape field. Then you can use any of the geometry functions available to that geometry type. This is a simple example that iterates over my parcels and looks for a polygon in the FLU layer that its centroid is inside of. parcel_desc=arcpy.Describe("parcels") #describe the parcels and get the shape field name parcel_shapefield=parcel_desc.ShapeFieldName flu_desc=arcpy.Describe("flu")#describe the flu and get the shape field name flu_shapefield=flu_desc.ShapeFieldName parcel_cursor=arcpy.UpdateCursor("parcels") for row in parcel_cursor: #iterate over the parcels     parcel_row_shape=row.getValue(parcel_shapefield) #get the geometry object     centroid=parcel_row_shape.centroid #get the centroid from the geometry object     flu_cursor=arcpy.SearchCursor("flu")     for flu_row in flu_cursor: #iterate over the flu         flu_row_shape=flu_row.getValue(flu_shapefield) #get the geometry object         if centroid.within(flu_row_shape)==True: #compare the two geometries             print "RENUM: %s  FLU: %s" % (parcel_row.A1RENUM, flu_row.FLU_CODE) #do some junk with the two rows     del flu_cursor del parcel_cursor ... View more

I have figured it out! Will post code later today once I get it nailed down. ... View more

Well you can iterate over the feature classes,   use a cursor to get a set of the values in the subtype field   iterate over the values in the set     select by the value     featureclasstofeatureclass the selection. ... View more

This sounds like a job for geometry objects. http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Geometry/000v00000095000000/ I cant help much beyond that as I am just learning how to use these as well. ... View more

This sounds like a job for geometry objects. http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Geometry/000v00000095000000/ I cant help much beyond that as I am just learning how to use these as well. ... View more

I dont like pythonwin. I find the GUI a bit irriatating for some reason. I use Komodo now. You can have multiple scripts open in tabs. Handy if you are working on a few things at the same time. ... View more

After some playing around I know how to make a point-geometry object. All you do is get the centroid from shape field. parceldesc=arcpy.Describe('parcels') parcelShapeField=parceldesc.ShapeFieldName parcel_cursor=arcpy.UpdateCursor('parcels') for parcel_row in parcel_cursor:     parcel_row_shape=parcel_row.getValue(parcelShapeField) #     centroid=parcel_row_shape.centroid and to compare that to another geometry I just need to do centroid.crosses(other geometry object) I dotn know how to get a polygon geometry from a row in a way taht is useful though. I can get a convex hull and an extent envelope but neither are helpful. ... View more

I have Leaning Python by O'Reilly. The 4th Edition covers Python 2.6 and 3.0. ArcGIS v10 uses 2.6. Also, #Python on irc.freenode.net is a great resource as well. Dont be daunted by the stuff they talk about. I ask noobish things all the time and they always take time to answer me. I agree that a class is good though. I got a class on a dvd from Keck and Wood for like 100 bucks thats a good intro to python for ArcGIS. EDIT: Also, all good python skill starts with a viewing of Monty Python's Quest for the Holy Grail. It puts you in the proper mind set. ... View more

Thanks Chris. I think this is what I want to do. Granted this is extremely metaish code lol. For update_row in update_cursor:   geo_update_row=create a geometry object for this row's label point   for search_row in search_cursor:     geo_search_row=create a geometry object for this row     if geo_update_row.crosses(geo_search_row) == True:       update_row.something = search_row.something       update_cursor.updaterow(update_row)     del geo_search_row     del geo_update_row Thats the general idea. Now I just have to learn geometry objects. ... View more

arcpy.AddJoin() This requires you to make a feature layer of your base table. the joined table doesnt need to be a feature layer or table view arcpy.CopyFeatures() This will copy your feature layer that you just joined to to a shp. ... View more

Im not sure about using the csv library to read, but if you open a file straight up with open(file,'r') and split on the ',' like Chris said you should get a list of strings regardless of whats in the strings. As for copying the file to a backup folder, you can use shutil.copyfile(source, destination) and then os.remove(source) which will copy your file and then delete the old one. I would not go into opening excel and mucking with win32com if you can avoid it. ... View more

WOO we win! Now lets not screw this up or we may not get the next thing we want. 😄 ... View more