topic Exporting Data of Different Projections in to a Single Feature Dataset in Geoprocessing Questions

Exporting Data of Different Projections in to a Single Feature Dataset

MANESK — Tue, 15 Apr 2014 06:35:10 GMT

I ve different shape files of UTM Projections accordingly belonging to zone 44,43,42..
I ve to club all these shape files into a single Feature dataset which asks for projection information while creating it in arcgis...
So which projection if i define, i can do the task.. Kindly suggest ...

Re: Exporting Data of Different Projections in to a Single Feature Dataset

PaulBeurskens — Tue, 15 Apr 2014 11:01:49 GMT

Hi

The feature classes all need to have thesame coördinate system otherwise it will not work.
Feature datasets can only store features with thesame coördinate system.
So first you will need to project your data (http://resources.arcgis.com/en/help/main/10.1/index.html#//00170000007m000000).

Depending how accurate your data needs to be you could use GCS WGS84 which has no zones but is geographical (GCS) in stead of projected (UTM).
Otherwise you will have to choose one of the zones and project all data in that so you can use this for the feature dataset (I advise you not to do this).

Greets

Paul

Re: Exporting Data of Different Projections in to a Single Feature Dataset

markdenil — Tue, 15 Apr 2014 12:18:09 GMT

The Merge tool will project your data on the fly, if each input is properly defined.
The output will be either the projection of the first input or
whatever the Output Coordinate System geoprocessing environment is set to.

While it is possible to 'get away' with merging data in adjacent UTM zones
(usually for features straddling the zone division
or features far to the north or south that physically fall into two or more zones)
(the zone edges overlap progressivly as one moves away from the equator)
It is indeed unlikely that a multi-UTM-zone merge would be a good idea.

Similarly, geographic (simple cylindrical) may not be ideal either;
it all depends on what you hope or expect to do with the data post-merge.
Some thoughtful consideration given to a projection choice at this stage
can accrue valuable advantages, and is well-advised.

Re: Exporting Data of Different Projections in to a Single Feature Dataset

PaulBeurskens — Tue, 15 Apr 2014 12:31:11 GMT

Merging features "across borders" sometimes creates more problems and also gives false extents.
Some databases or feature datasets will not accept the data becouse it is "out of bounds" or exceed the "spatial grid index" (see also: http://resources.arcgis.com/en/help/main/10.1/index.html#//01m600000046000000)

But putting it from UTM to GCS also is not allways the best option, but it will work without problems and is geographicly correct.

Why is it necessary to put it in a Feature dataset, do you want to check the topology?

Re: Exporting Data of Different Projections in to a Single Feature Dataset

RyanClancy — Tue, 15 Apr 2014 14:19:47 GMT

I'll echo what Paul said. Unless you specifically need to build a topology, a network dataset, a terrain dataset or a geometric network, don't use a feature dataset. Just put the data in your geodatabase. By definition, all feature classes in a feature dataset must have the same spatial reference.

http://resources.arcgis.com/en/help/main/10.1/index.html#//002300000001000000