Class to define similarity transformations to be applied on sp objects. Similarity transformations can rotate, shift and scale geometries.
Objects can be created by calls to the function SimilarityTransformation.
controlPoints
:Object of class "data.frame"
containing
control point coordinates arranged in four (4) columns: X source,
Y source, X target, Y target.
parameters
:Object of class "numeric"
. A vector of four
(4) parameters for representing the transformation, namely: a, b, c and
d, where
x' = ax + by + c
y' = ay  bx + d
residuals
:Object of class "matrix"
. Only set if Least
Squares is applied, i.e., if more than two (2) control points were
provided. Residuals are the difference between transformed source
coordinates and target coordinates of control points.
rmse
:Object of class "numericOrNULL"
. Only set if
Least Squares is applied, i.e., if more than two (2) control points were
provided. Root Mean Square Error, useful when comparing two
transformations. It measures the general deviation of transformed source
coordinates with respect to target coordinates of control points. It has
the same units as the coordinates, usually meters.
Class "Cartesian2DCoordinateTransformation"
, directly.
signature(object = "SimilarityTransformation")
:
Calculate
transformation parameters from control points.
German Carrillo
Iliffe, J. and Lott, R. Datums and map projections: For remote sensing, GIS and surveying. Section 4.5.3. pp.113115, 2008.
1  showClass("SimilarityTransformation")

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