Coordinate Point Conversion

Instructions for use

If the user needs to transform the Coordinate Transformation of a point into the coordinate in another coordinate system, the Coordinate Point Conversion "function can be used for transformation to obtain the coordinate value of the point in another coordinate system.

The Coordinate Point Conversion supports the communication between two Geographic Coordinate System, between two Projected Coordinate System, At the same time, it also supports the conversion between Geographic Coordinate System and Projected Coordinate System.

Function entrance

  • Start tab-> Data Processing group-> Projection Transformation drop-down Button-> Coordinate Point Conversion.

Operating instructions

  1. Source Data Point: directly input the longitude and latitude or X/Y coordinate value of the point. If the Source Coordinate Point is projected as Geographic Coordinate System, it can also be switched to "Display in the form of degree: minute: second", and input the specific value of the longitude and latitude of the point coordinate.
  2. Source Coordinate System: You can set the coordinate system of the source data at Source Coordinate System. The Coordinate Point Conversion feature does not support planar Coordinate Transformation. The source and Target Dataset coordinate systems can only be set to Geographic Coordinate System or Projected Coordinate System. There are three methods for Coordinate System Settings:
      • Reset coordinate system: Click the Reset coordinate system button and select More from the drop-down menu to set the target projection in the Coordinate System Settings dialog. Please refer to Projection Settings for the specific operation of Coordinate System Settings.
      • Copy Coordinate System: Click the Copy Coordinate System button to select Copy from Datasource or Copy
        • from Dataset:
      • Import Coordinate System: Click the Import Coordinate System.. button to select the Projection Info File and import it.
  3. Target Coordinate System: a Result Coordinate Point Projected Coordinate may be set at the Target Coordinate System, The resulting Coordinate System Settings is a Geographic Coordinate System or Projected Coordinate System that is different from the Source Coordinate System, The setting mode is consistent with that of Source Coordinate System Projection Settings.
  4. Reference Conversion Settings: Click the Drop-down Button on the right side of the Conversion Method tab, and the drop-down menu list will display more than ten Projection Transformation methods provided by the system. The user can select an appropriate Projection Transformation method. For a description of the conversion method, refer to the Description of reference frame conversion method .
  5. Projection Transformation Parameters: Select different conversion methods. The parameters that can be customized in the Projection Transformation dialog box are different. For the introduction of different Projection Transformation methods, please refer to the Description of reference frame conversion method .
    • When a three-parameter transformation method is selected, such as Geocentric Transalation, Molodensky, or Molodensky Abridged, The Projection Transformation "dialog box needs to set the parameters for the offsets in the X, Y, and Z directions.

      The user needs to set three translation parameters, namely (.DELTA.X.DELTA.Y.DELTA.Z). This transformation is essentially a geocentric transformation from the center of one datum (0,0,0) to the center of another datum (ΔX, ΔY, ΔZ). A three-parameter transformation is a linear translation in meters.

    • When the seven-parameter conversion method is selected, such as Position Vector, Coordinate Frame or Bursa-wolf, it is necessary to set the parameters of scale difference, Rotation angle and offset.

      The user needs to set seven parameters, namely, three linear translation parameters (.DELTA.X.DELTA.Y.DELTA.Z), three angle parameters of rotation around the axis (Rx, Ry, Rz), and a scale difference (S). The translation parameter is in meters; the rotation parameter is in angular seconds; and the scale difference is in parts per million (ppm).

  6. Import/Export Projection Transformation Parameter File: Click the Import button below the Projection Transformation dialog box. You can import a Projection Transformation Parameter File with a suffix of *.ctp to import the parameter information saved in the Projection Transformation Parameter File. Parameter Settings as the current Projection Transformation; Click the Export button below the Projection Transformation dialog box to export the parameters currently set in the Projection Transformation dialog box to the specified path, and then import them when needed.
  7. After completing each Parameter Setting, click the "Conversion" button to complete the operation of Coordinate Point Conversion. You can view the Coordinate Point Conversion result at Result Coordinate Point in the Coordinate Point Conversion dialog box. If the Target Coordinate System is the Geographic Coordinate System, the Result Coordinate Point coordinate can be displayed in the form of degree: minute: second.
Note:
    The
  • Coordinate Point Conversion is performed between different Geographic Coordinate System or Projected Coordinate System, If the Source Coordinate System is the same as the Target Coordinate System, the conversion will not be performed, and a pop-up box prompt "Coordinate Point Conversion Failed" will be displayed.
  • In practical work, which conversion method is used depends on the specific situation. For the determination of each parameter, please purchase authoritative measurement data, or verify the correctness of the parameters through the coordinates of the known control points in the two Coordinate Systems.

Related topics

Dataset Projection Transformation

Batch Projection Transformation

Model Transformation Parameter Calculation