Add or Edit a Transformation Set

Description

Add or edit coordinate pairs and compute transformation parameters.

Access

Home / Tools / Modify / Transform / Insert a new item or Edit selected item

Requirements

Controls

General Controls	Description
Name	Type a name for the transformation.
Transformation Type	Select the type of transformation to compute parameters for: 2D Shift - A shift in the x and y direction. 3D Shift - A shift in 3 dimensions. 2D Conformal (Unscaled) - A two dimensional conformal coordinate transformation with a scale factor of 1.0. 2D Conformal (Scaled) - A two dimensional conformal coordinate transformation. 2D Conformal (Scaled) with Height - A two dimensional conformal coordinate transformation with a height shift. 3D Conformal (Unscaled) - A three dimensional conformal coordinate transformation with a scale factor of 1.0. 3D Conformal (Scaled) - A three dimensional conformal coordinate transformation.
Description	Type a description for the transformation.

Control Points	Description
Use Weighting	Do one of the following: Select the checkbox to assign different weights to the coordinate pairs Clear the checkbox to use a default weight of 1.0 for all coordinate pairs.
	Add a new coordinate pair to the list.
	Delete the selected coordinate pairs from the list.
	Find the selected point or vertex in the project and load its coordinates.
Compute	Compute the transformation parameters.
OK	Add or update the transformation set.
Cancel	Close without saving the changes.

Columns available in the point list, depends on the Transformation Type selected.

Column	Description
From	Details of coordinates in the From system.
To	Details of coordinates in the To system.
Weight	If you selected Use Weighting, type the weight to be assigned to the coordinate pair.
Included	Do one of the following: Select the checkbox to include the coordinate pair from the computation. Clear the checkbox to exclude the coordinate pair from the computations.
Name	Input either the name of the point with the coordinates to use or the unique id of the vertex using the syntax Id:unique ID.
Easting	Input the easting coordinate.
Northing	Input the northing coordinate.
Height	Input the orthometric height.

Notes

Transformation parameters are computed from coordinate pairs that have values in both the From and To coordinate systems.
To input a 2D coordinate for a transformation with a height shift, clear the Height for both the From and To point.
For 3D transformations, all coordinates must be 3D.
Type the Name of a point and press to have the coordinates loaded from the project.
You can use the mouse to select a vertex from the model view and have the coordinates loaded from the project.
You can tentatively select a vertex from the model view and view the vertices coordinates in the grid prior to accepting them as control.
A transformation can be computed automatically on import if points with the same name exist in the project and the imported data file.

Possible errors

Errors or Warnings	Description
The computation has no solution.	There is not sufficient data to compute the solution.
The transformation residuals exceed the tolerance. Save anyway?	The computed residuals indicate that there is an error with coordinates entered or the selected transformation type is not suitable for the data. Click Cancel to return to transformation point list and resolve the issue.