multi-Clip in ArcGIS 10?

Question

Hi all
  I have a question in my project! The thing is that : I have two maps, one is a polygon map of cities (area of cities) at global scale. another one is a adminstrative boundary map (also at global scale).  Now I need a function or tool to multi-clip area of cities according to the boundary map. For example, A (area map) as a input layer and B,C,D,E,F.... (boundary map with different selected countries) as a clipped map. I knew that Clip function can work well with one clipped layer but cannot work with multi-tasks (for example if I would like to clip 50,100 cities or even more in same times). I just wonder if there was any function or code that can make this possible?

If you have any suggestion or idea, I would give all my thanks to you!

wusirui · Answer

You say you have a cities "map" and an administrative boundary "map".
I assume you mean that you have polygon shapefiles or geodatabase feature classes:
the cities file has polygons with some sort of ID (name of the city, perhaps)
The admin area file has polygons with admin area IDs (the name of the country, for example).

In ArcToolbox, in the Analysis Tools > Overlay section is a tool called Union
read the help on that tool.
It will show you how you can get one set of polygons (in a new file)
that has the shapes and attributes from both the other two files.

Now you can use any of a variety of tools to select whatever polygons you want to use;
say, the cities in Utopia, using a Select By Attribute operation.

You can make a layer, using your query (example: cities in Utopia), that show just the features you want.

If you need separate files of each set, you can copy the data out to a new file
(but, as you write, you will then have more than 100 individual files).

The union is just one operation; you then get a data set you can look at different ways to get all the different 'maps' you want.
Doing it with clipping will require a lot more work:
first select or make the hundred or more layer files of individual countries
Then perform the hundred or more clips.

Best of luck

Thank you for your suggestion! 🙂

markdenil · Answer

You say you have a cities "map" and an administrative boundary "map".
I assume you mean that you have polygon shapefiles or geodatabase feature classes:
the cities file has polygons with some sort of ID (name of the city, perhaps)
The admin area file has polygons with admin area IDs (the name of the country, for example).

In ArcToolbox, in the Analysis Tools > Overlay section is a tool called Union
read the help on that tool.
It will show you how you can get one set of polygons (in a new file)
that has the shapes and attributes from both the other two files.

Now you can use any of a variety of tools to select whatever polygons you want to use;
say, the cities in Utopia, using a Select By Attribute operation.

You can make a layer, using your query (example: cities in Utopia), that show just the features you want.

If you need separate files of each set, you can copy the data out to a new file
(but, as you write, you will then have more than 100 individual files).

The union is just one operation; you then get a data set you can look at different ways to get all the different 'maps' you want.
Doing it with clipping will require a lot more work:
first select or make the hundred or more layer files of individual countries
Then perform the hundred or more clips.

Best of luck

wusirui · Answer

That is a lot of clipping.
You will want to use a loop in model builder or python to do things that way.

I would suggest, however, something simpler
like union-ing the two polygon feature classes

This will add the admin area attribute to the city area polys

now, using the attribute of the admin area, 
and the city attribute,
you can select the cities in a particular admin zone
as a layer (or a selection)
and export or copy just those polygons to a new featureclass, (if you want)

Again, I would suggest just leaving all the intersected data in one FC
and making individual layers as you need them.

Hi, the thing is that I probably need over 100 different countries so it could be hard to clip like what you suggested. Do you know if there was any python or model way to solve? I dont have any background in PC language but I think I could also consider this part if necessary.