Altering Shapefile's Projected Location

Being able to compare the physical dimensions of a shapefile to a more familiar location would be an ideal tool for any group interested in GIS management of something such as land development. Being able to visually compare the properties of shapfiles layered on top of each other would be an effective tool in order to persuade an audience.

In this guide, I will explain the process in order to compare the size of a Florida lake, Okeechobee, to other bodies of water.

               

Starting off, I created a shapefile-polygon in ArcCatalog, and opened the file in ArcMap. I started an editing session, where I roughly outlined the shape of the lake and altered its transparency so it’s easier to follow.


After your shapefile is placed on the map, it’s ready to be moved.

In your editor toolbar, start editing. Under the ‘editor’ drop down menu>more editing tools>spatial adjustments.

Select under the spatial adjustment menu, set adjustment data and choose all features in this layer. Making sure that the object you’re trying to move is selected.

Then select in the same dropdown menu, adjustment methods, and choose affine transformation. The affine transformation follows a specific equation to set it’s rotation and skew properties, but changing the scale and rotating it dismisses out point, so we have to follow a specific trick to get it to not do anything.

The affine method needs a couple reference arrows, but if you choose the same location it shouldn’t be a problem. So click new displacement and click your shapefile on an edge close to its axis (North, south, east, west) and then drag the arrow to the same axis of the location you would like to displace your shapefile on.

So, let’s compare Lake Okeechobee, to Deep Creek Lake, in Maryland.


First, draw a line from the North end of your Object to the North End of your destination. Then you have to copy the line (ctrl-c) and paste it four times (ctrl-v x4), and then delete the original arrow (I’m not sure if that’s entirely necessary, but it seems appropriate)

Then click the spatial adjustment menu and click adjust. If this button is blanked out, be sure that you chose the appropriate layers. Other wise it will move after a slight pause.


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