Adjustment Computations Adjustment Computations: Spatial Data Analysis

CHAPTER 18

Two-Dimensional Conformal Coordinate Transformation

Introduction

The least squares method can be used in any situation where mathematical relationships between observations and unknown parameter are known. An example of this transformation is discussed in Section 18.8. This worksheet demonstrates how to develop observation equations for a least squares adjustment of the data.

Data file

Parsing the Data File

Data file shown to right

Id

Control coords

Measured coords

The following to statements set the standard deviations for the measured coordinates to the user-entry value for a weighted adjustment, or 1 for a unweighted adjustment.

Results of parsing

Least squares solution

Solution:

Adjusted observations:

Residuals:

The standard deviation of unit weight:

Propagate errors to adjusted observations

Adjusted Parameters

Parameters

t values

±

±

±

Adjusted Observations

Matrices:

Transform Other Points

Loop through points to transform and build A matrix

Transformed points and

covariance matrix for adjusted observations

Place in Results matrix

Set coordinates

Set uncertainties

Reset H for reuse.

 

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