Assign Coordinate System

The Assign Coordinate System dialog is accessed from several locations. Often it is opened by clicking the Set button in the layer Coordinate System Properties page or the Change button in the map Coordinate System Properties page. It links a file, map layer, or map to a specific coordinate system. Once a coordinate system is defined for a file, a Golden Software Georeference .GSR2 file is created. This file contains all the relevant coordinate system information that Surfer needs to load the file in the proper coordinate system in the future.

When a .GSR2 file is created for a data file, it is read when creating grids or maps from the data file. The resulting grid or map layer has the same coordinate system as the original data file. The projection information can be saved with the grid file using the Spatial References options. It is recommended to check the GS Reference (Version 2) file if you intend to use the grid file in Surfer, as the GSR2 retains all of the information needed.

Assign Coordinate System Dialog

Assign a coordinate system to a map, layer, or file in the Assign Coordinate System dialog.

Assign a projection to your file or map layer in the Assign Coordinate System dialog.

Search for Coordinate Systems

Surfer has over 2500 coordinate systems in the Assign Coordinate System dialog. To search for a specific coordinate system type a partial name, complete name, or EPSG code into the Search for text or EPSG code field. Next click the button or press ENTER to search for the coordinate system. The number of returned search results will be displayed below the search bar. The search results will replace the full coordinate system list. Navigate through the search results by clicking the button to expand the categories in the Assign Coordinate System dialog. Click the button to clear the search results and display all of the coordinate systems in the Assign Coordinate System dialog.

When searching in the Assign Coordinate System dialog, the search string must exactly match a portion of the desired coordinate system name or EPSG code. However, the search string does not need to be the complete name or EPSG code. For example, searching for System 1984 will return the World Geodetic System 1984 coordinate system, but searching for World 1984 returns no results.

Projection Categories

Click the button to expand the options in the Assign Coordinate System dialog. Click the button to collapse the options.

Local System

Expand Local System to select the Unreferenced local system, which contains a Projection of None, a Datum of None, and a Warp of None. For example, you may have a data set with an arbitrary coordinate system (i.e. not real world X, Y coordinates). You would assign this data to a Local System , if a coordinate system is necessary.

Predefined

Expand the Predefined section by clicking the + button. The Predefined section includes all coordinate systems that have been predefined for Surfer.

Geographic (lat/lon)

Expand Geographic (lat/lon) to select a Latitude/Longitude coordinate system and datum that fits your needs. Detailed information about each projection is listed at the bottom of the dialog when the system is selected. If your data are currently in a form of lat/lon, you would want to select one of the options in Geographic (lat/lon).

Projected Systems

Expand Projected Systems to select a predefined Polar/Arctic/Antarctic, Regional/National, State Plane, UTM, or World coordinate system. Detailed information about each projection is listed to the right when the datum is selected.

Templates

Expand the Templates section to select a predefined template. Click the desired template and press the Modify button to change the properties. Once modified, the new coordinate system is added to the Custom section.

Favorites

Select a coordinate system and click the Add to Favorites button to add a coordinate system to your Favorites list. Alternatively, right-click on a selected coordinate system and choose Add to Favorites from the menu. Select a coordinate system and click the Remove from Favorites button to remove a coordinate system from your Favorites list. By default, no favorite coordinate systems are specified. It is recommended that systems that you use frequently and Custom systems that you intend to use more than once be added to the Favorites section for ease of navigation.

Custom

Expand Custom to see the custom coordinate system you have defined for the current file. Custom systems can be defined by clicking the New button. By default, no custom coordinate systems are specified. Custom coordinate systems are only listed in the dialog when the file using the custom coordinate system is open.

If a Custom coordinate system is defined and intended to be used more than once, it is highly recommended that the system be added to the Favorites section by clicking the Add to Favorites button.

New Local Coordinate System

The linear units and offsets can be specified for local coordinate systems. Click the New Local System button to open the Define Unreferenced Coordinate System dialog and define a custom local unreferenced coordinate system. Alternatively, click the Modify button while Unreferenced local system is selected in the Select coordinate system list to open the Define Unreferenced Coordinate System dialog.

New Geographic Coordinate System

Click the New Geographic System button to open the Define Coordinate System dialog and define a custom projection and datum. Alternatively, right-click on an existing coordinate system and choose New Geographic System to create a new projection based off the selected projection. The new custom projection and datum will be listed in the Custom section with the name you defined.

Modify Coordinate System

Select any coordinate system from the Select a coordinate system list. Click the Modify button to open the Define Coordinate System or Define Unreferenced Coordinate System dialog. Alternatively, right-click on the coordinate system and choose Modify from the menu. Modify any properties and click OK. The modified coordinate system is added to the Custom list.

If the Modify button is unavailable, make sure that a specific coordinate system is selected. If a category of systems, such as Predefined or Geographic (lat/lon) is selected, the Modify button is unavailable.

Add to Favorites

Click the Add to Favorites button to add a projection to your Favorites list. Alternatively, right-click on a coordinate system and choose Add to Favorites. This is very useful if you frequently use the same projection, such as World Geodetic System 1984. This is also useful for Custom systems that will be used on multiple project files. Adding the projection to the Favorites list makes selecting the projection easier in the future.

If the Add to Favorites button is unavailable, make sure that a specific coordinate system is selected. If a category of systems, such as Predefined or Geographic (lat/lon) is selected, the Add to Favorites button is unavailable.

Remove from Favorites

Select a coordinate system in the Favorites list and click the Remove from Favorites button to delete the system. Alternatively, right-click on a coordinate system in the Favorites section and choose Remove. The coordinate system is removed from the Favorites section.

If the Remove from Favorites button is unavailable, make sure that a specific coordinate system is selected in the Favorites list. If a category of systems, such as Predefined or Geographic (lat/lon) is selected or if a coordinate system is selected in a category other than Favorites, the Remove from Favorites button is unavailable.

Load from File

Click Load from File to load a coordinate system from a spatial reference file with the Open dialog. The following file types are supported for import:

Golden Software Reference .GSR2
Golden Software Reference .GSR
Esri Projection .PRJ
Well Known Text .WKT
Esri Auxiliary .AUX.XML

Save to File

Click Save to File to save a predefined or custom coordinate system to a spatial reference file with the Save As dialog. The following file types are supported for export:

Golden Software Reference .GSR2
Esri Projection .PRJ
Well Known Text .WKT
Esri Auxiliary .AUX.XML

Example 1: Select a Predefined Coordinate System (i.e. UTM)

In the Assign Coordinate System dialog, click the button to the left of Predefined.
Click the button to the left of Projected Systems.
Click the button to the left of UTM.
Click the button to the left of WGS84.
Select WGS84 UTM zone 13N.
Click OK . The projection for this data is now set to WGS84 UTM zone 13N.

Example 2: Create and Select a Custom Coordinate System (i.e. Lambert Conformal Conic)

In the Assign Coordinate System dialog, click the New button to open the Define Coordinate System dialog.
Change the Name to Lambert Conformal Conic Custom.
From the Projection list, select Lambert Conformal Conic.
Make any necessary changes to the Parameter or Values in the Projection section.
Make any necessary changes to the Datum section.
Click OK and the Lambert Conformal Conic Custom projection is added to the Custom section.
Click the custom projection and click OK to apply the projection to the data.

Example 3: Saving a Custom Coordinate System

In the Assign Coordinate System dialog, click the button to the left of Custom.
Select the coordinate system in the Custom section and click the Add to Favorites button.
Click the button to the left of Favorites to open the Favorites section. The custom projection is saved here.
Click OK to close the dialog.

Assign Coordinate System