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I'm trying to collapse all divided roads in one centreline and to integrate any other spurs or errors in the dataset to create one set of centrelines. I have used Merge Divided Roads but it leaves a lot to be desired (most of the roads I wanted collapsed did not merge).

Here is the dataset: enter image description here

And here is what happens when it is collapsed: enter image description here

I have also repaired geometry, reprojected and made it into a singlepart feature but nothing seems to work. I have tried it on multiple computers.

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How many features are in this dataset? To collapse the centerlines you need the individual roads to be features, but your reference to a "singlepart feature" suggests that maybe the dataset is just a single feature, where collapsing will either fail or give strange results. – whuber Sep 23 '11 at 16:23
whuber - the function won't run unless it's had "multipart to singlepart" feature. It happens even if I don't alter the file – Emily Sep 23 '11 at 16:26
I suspect you need to merge multipart roads into single parts. If you merged everything into a single feature, it's amazing the script didn't just fail outright; I doubt it would be able to succeed on something so complex. Have you tested out the script on a single-part feature representing just one street? – whuber Sep 23 '11 at 16:27
It isn't a single feature... like I said I used this function:… – Emily Sep 23 '11 at 16:31
To clarify: is it, or is it not the case, that your dataset represents each individual road as a single part feature? When you ran the collapse-centerline script, how many records were shown in the attribute table? – whuber Sep 23 '11 at 16:36
up vote 0 down vote accepted

Just to write something so it is known how it worked out. I ended up being able to get Merged Divided Roads to work, and did not end up using the Collapse tool. Thank you everyone for your help.

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