This example WGS84 geographic coordinate system converted from the projected coordinate system Xi 80 (central meridian 114, with three degrees projection) is provided a plurality of sets of control points, we choose the uniform distribution of the three sets of control points involved in the calculation.
Seven-parameter conversion tool: COORD
Data conversion tools: ArcGIS toolbox
1-- seven-parameter calculation
Note: If a more than 5 control points, seven parameters are not provided by this calculation method; calculating tools COORD.
First, set up the projector, the present embodiment the central meridian of 114 degrees with Gauss projection 3
Coord seven parameters used to calculate calculation tool, select the calculation below seven parameters
Three sets of input control points, B for latitude, L representative of the longitude, H is the height; X and Y are generally omitted out large numbers, where the control point 38 will be omitted in the X, Y 4 is omitted, the need to manually add back;
Click computing
Then click the OK button, the result is the seven-parameter calculation, save the result. Accuracy may be calculated by other control parameters involved in the calculation of checkpointing.
Note: the rotation angle (the XYZ) derived seven parameters calculated txt file three values are in degrees, and the second unit is frequently applied.
2 - Create custom coordinate transformation
Open the red box ArcGIS tools, data management tools -> Projections and Transformations -> Create custom geography (coordinates) transformation
Geographic transformation name: here named wgs84toxa80, behind the conversion will use this name.
Enter the geographic coordinate system: selecting wgs84 coordinate system.
Output geographic coordinate system: selecting xian80 three degrees with the projection 114 of the central meridian projected coordinate system.
Custom conversion method: selecting COORDINATE_FRAME (seven-parameter conversion method), the converted input parameter in the following seven parameters. Click OK.
3 - coordinate transformation vector data
Open ArcGIS red tool box, data management tools -> projection and transformation -> Vector -> Projection
Input data or feature class: select a data source coordinates dataset wgs84
Output data set or feature classes: Selects the output directory for the conversion
Output Coordinate System: Select the target Xi'an 80 coordinate system
Geographic coordinate transformation: We choose to create good geographic coordinate system transformation wgs84toxa80, and click OK
4 - raster data coordinate transformation
Open ArcGIS red tool box, data management tools -> projection and transformation -> Raster -> Project Raster
Input parameters are the same vector projection.