A spatial reference is the georeferencing and coordinate system assigned to any geographic data.
A schematic diagram template also has a spatial reference that defines the coordinate system x,y domain for all the schematic diagrams it implements.
The spatial reference specified at the diagram template level is needed for schematic layout algorithms so they operate on a consistent coordinate system. The spatial reference set on a schematic diagram template determines the spatial reference for all diagrams implemented by the diagram template—this spatial reference is the same for all diagrams based on a schematic diagram template.
The following section explains how to set or modify the spatial reference on a schematic diagram template. This operation is done in the Catalog window.
- Start ArcCatalog.
- Navigate through the Catalog tree and select the schematic dataset that contains the desired schematic diagram template.
- Right-click this schematic dataset in Catalog tree and click Show/Hide Schematic Classes.
New main branches, one per schematic diagram template in the schematic dataset, automatically appear in Catalog tree. They display with the following icon at their left:
- Right-click the entry corresponding to the schematic diagram template on which you want to specify a spatial reference and click Properties.
The Schematic Diagram Template Properties dialog box opens.
- If it is not already active, click the XY Coordinate System tab.
- To specify a coordinate system or modify the existing coordinate system, you have several possibilities:
- Selecting an existing coordinate system
- Click the Select button.
- Navigate to the coordinate system you want to use.
For example, you can use one of the predefined coordinate systems in the Coordinate Systems folder that was provided with ArcCatalog, or you can use a projection file that was created with ArcInfo Workstation.
- Click the coordinate system.
- Click Add.
- Importing a coordinate system
- Click the Import button.
- Navigate to the data source whose coordinate system parameters you want to copy.
For example, you can get coordinate system information from coverages, rasters, or feature datasets and feature classes in a geodatabase.
- Click the data source.
- Click Add.
- Defining a new geographic coordinate system
- Click the New button and click Geographic.
- Type a name for the new geographic coordinate system.
- Type the appropriate semimajor and semiminor or inverse flattening values, then type a name for your custom spheroid and datum. Alternatively, click the Datum or Spheroid drop-down arrow and click a predefined datum or spheroid.
- Type the appropriate radians per unit, then type a name for your custom units. Alternatively, click the Angular Unit drop-down arrow and click a predefined unit of measure.
- Type the appropriate degrees, minutes, and seconds defining the prime meridian, then type a name for this line of longitude. Alternatively, click the Prime Meridian drop-down arrow and click a predefined line of longitude.
- Click OK.
- Defining a new projected coordinate system
- Click the New button and click Projected.
- Type a name for the custom coordinate system.
- Click the Projection Name drop-down arrow and click one of the supported projections.
- Type the appropriate parameter values for the projection.
- Click the Linear Unit drop-down arrow and click a predefined unit of measure. Alternatively, click <custom> in the drop-down list, type the appropriate meters per unit, then type a name for your custom units.
- Specify the projection's datum by selecting a predefined geographic coordinate system or defining a new geographic coordinate system. Afterward, you can modify the geographic coordinate system's parameters if you want.
- Click OK.
- Modifying a coordinate system's parameters
- Click the Modify button.
The Geographic or Projected Coordinate System Properties dialog box appears.
- Follow the steps for defining either a new geographic or a new projected coordinate system to change the appropriate parameters.
- Click OK.
In all cases, at the end of this step, the coordinate system is fixed. Its parameters are listed in the Details box.
- Click OK on the Schematic Diagram Template Properties dialog box.
The spatial reference set on the schematic diagram template is now fixed. It will determine the spatial reference for all diagrams implemented by this diagram template—this spatial reference will be the same for all diagrams based on that schematic diagram template.