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Appendix 2. Order of Operations

To demonstrate the impact of order of operations using add, delete and/or move functions, we compared the difference of correction factors using different orders of operations to get the same locations of break points. Let us assume there are 4 break points (x1,x2,x3,x4) and the corresponding correction factors are f1,f2,f3,f4 and f5 respectively. The plot starts out as follows:

We wish to end up with a plot that looks as follows:

There are 3 ways we could achieve this, 1) by moving break point x2, 2) by adding a break point at the new position and then deleting break point x2, and 3) by deleting break point x2 and adding a new break point at the new position. These 3 options could result in different correction factors for the segments as can be seen as follows:

Option 1: Moving the break point

Before moving break point x2

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x2f2
3x2x3f3
4x3x4f4
5x4endf5

After moving break point x2

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1new x2f2
3new x2x3f3
4x3x4f4
5x4endf5

Option 2: Adding the break point x5 and deleting the break point x2

Before doing any operations

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x2f2
3x2x3f3
4x3x4f4
5x4endf5

After adding break point x5

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x2f2
3x2x5f3
6x5x3f3
4x3x4f4
5x4endf5

After deleting break point x2

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x5f2
6x5x3f3
4x3x4f4
5x4endf5

Option 3: Deleting the break point x2 and adding the break point x5

Before doing any operations

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x2f2
3x2x3f3
4x3x4f4
5x4endf5

After deleting break point x2

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x3f2
4x3x4f4
5x4endf5

After adding break point x5

Segment IdStarting PointEnding PointCorrection Factor
10x1f1
2x1x5f2
6x5x3f2
4x3x4f4
5x4endf5


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