Adjustment Computations Adjustment Computations: Spatial Data Analysis

SECTION 18.5

Two-Dimensional Affine Coordinate Transformation

Introduction

The two dimensional affine coordinate transformation takes points in one coordinate system to another using two scale factors (affine), two rotations, and two translations. It is described in Section 18.5 of the book, Adjustment Computations: Spatial Data Analysis. The transformation requires a minimum of 3 points known in xy coordinates in both coordinate systems. This worksheet demonstrates this problem. The data file is read and parsed into input tables, matrices computed, and the least squares solution determined.

Library file

Read data file

Parse control data

Parse observed data

Compute A, W, and L matrices

Solve problem

Compute residuals

Build results table

Transform points and propagate errors

 

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