Latest Contributions by DuncanHornby

David, Can you zip up some sample data that it fails on for others to review? Duncan ... View more

Just a guess here, but could it be possible that the feature to polygon tool is generating a Feature Class that contains no data?  A newer geodatabase will support a higher level of precision and so none of your polylines form polygons, whilst an older geodatabase has a lower level of precision and everything "snaps" to form enclosed areas? Duncan ... View more

David, So let me get this straight. At some point your model generates 2 layers each containing 1 polygon and you are using the spatial join tool on these? Have you tried to use the spatial join tool on these layers only (so not part of any model) to see what happens? If these polygons are not top secret maybe you can zip them up and post on this thread? Duncan ... View more

Neil, I had a play with the eval() function and was able to replicate the issue you have. For what it's worth I couldn't work out how to get it to call the function, it must be quirk of VBA in ArcMap. Duncan ... View more

Neil, I've never been able to find information about the underlying algorithms used by ESRI geoprocessing tools. Unless they are misbehaving, who cares how they do it as long as they are fast and accurate? As I understand your initial description you have 1 shapefile with a single polyline in it and you are trying to find the intersection points in many polygon shapefiles, is this correct? If so how many shapefiles are you talking about? You could consider using in_memory layers if you are generating a few layers with a few points as a way of speeding things up? Duncan ... View more

Roger, I just tried the following code on a river network I have and it did not produce an error. # Layer name in Map Document s = "Rivers" # Describe object and print name string to confirm it worked desc = arcpy.Describe(s) print desc.namestring # Get spatial reference and print name sr = desc.spatialreference print sr.name # Get FeatureClass and check if M aware fc = desc.featureclass print fc.hasm # Set M domain sr.setmdomain( -1000,1000) This would suggest that there is something odd with your layer as your code looks sound? Duncan ... View more

Why don't you call the Intersect Tool via the IGeoProcessor to create all intersection points in one hit rather than looping with a spatial filter? If you need attribute information say from the polyline dataset you could then call the spatial join tool? Duncan ... View more

Johan, Check out the HYDROSHEDS website. Duncan ... View more

Claire, Once you have converted your RAW lidar data into a DEM you'll need to fill in sinks before you create the flow accumulation and flow direction grids. I don't have ArcHydro currently installed but I remember it has a fairly comprehensive Help document to guide you. For a high level step by step guide of how to generate watersheds have a look at this section of the ESRI help. Duncan ... View more

Have you looked at the ArcScripts website? Look at this, it may need tweaking to get it working as it is for an earlier version of ArcView, or it may just work, I've not tried it. http://arcscripts.esri.com/details.asp?dbid=15877 Duncan ... View more

Chris, I'm not too hot on this subject but I've always understood dpi (dots per inch) as something that output devices use (printers/screens) so dpi has no meaning when you look at a raster and is probably why there is no interface that exposes such a property.  I came across this web page which tries to explain what dpi is. Your thread title also suggests you want to know about cell size, if so then use the interface IRasterInfo. Duncan ... View more

Well the logic is not that dissimilar. You still need to get a handle on the FeatureClass and use a FeatureCursor to query your dataset by setting the WhereClause. This would return the feature or "row" where you could extract the geometry and zoom to it. But you are opening up a can of worms here.  "Bob Street" is not the same as "bob st." or even "Bob Stret". Can you rely on your users entering the correct text? I can answer that now, no! I'm sure someone could add stuff to this thread about using regularly expressions? ... View more

Are you saying that you want drop-down lists of street names that the user can select? If so you want to be using a COMBOBOX not a TEXTBOX, the logic is: Get a handle on the Map (IMap) Get a handle on the layer (ILayer) Create a point of type IFeaturelayer to your Layer Get the Featureclass of the FeatureLayer Create a FeatureCursor over entire FeatureClass Step through Each Feature reading street name field Add the street name to a list ensuring it's not duplicated, you could use a dictionary for this Write the contents of the dictionary to a COMBOBOX ... View more

Steve, Well not sure whats going on then. Before your organization "neuters" you in their pursuit of "upgrade perfection" I would try the following. If you have access to a 9.3 machine I would use arc catalog to create a file based toolbox (a tbx file) and then use arc catalog to copy your models into it so you get them out of your file geodatabase. Hopefully version 10 then will see them. You should then be able to import them back into your upgraded v10 file geodatabase. Duncan ... View more

Patrick, Gut feeling is that it's probably an Excel thing. Are all you 1000's of worksheets in a consistent  format?  I recently had a problem with Excel and it turned out to be some bizarre Asian characters in a cell that looked perfectly normal. You don't indicate when it bombs out, has it done some processing then blows up or bombs out immediately? If you are using ArcGIS 10 may be you could use an iterator to loop rather than batch up a tool as at least this may give you a hint at what point it bombs out at? Duncan ... View more