Geoida |
Linear/Affine Transformation |
This transformation is basically an isogonal affine transformation in two (horizontal) dimensions, i.e. (a) linearity is preserved because the scale is the same in both dimensions, (b) angles are preserved (isogonic), and (c) parallel lines remain parallel (affinity), or in simple terms, a 2D linear transformation involving translation, rotation and uniform scale change. An optional height adjustment is also included but is not subject to scale change. The transformation is applied locally with no change to datum or coordinate type.
IMPORTANT - ALWAYS verify the accuracy and reliability of a transformation before applying to critical data - always test first with points whose coordinates are known in both systems. |
General Transformation Principles
General transformation principles will be found under the main topic for this section, Data Transformations - General.
Definition
A Linear/Affine transformations is defined locally within the Select Transformation window only and is preserved within the job database.
Point heights
Points do not require valid heights unless a non-zero vertical shift (Height change field) is also applied. The vertical datum remains the same (cannot be changed).
Further Details
Further details of the transformation options will be found in the Transform Job topic.
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