Automatic generation of elevation data over Danish landscape

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2 Methods of determining elevation data
The adjustment system is now set up, the observation equations have to be defined. For all points placed
in the first mesh (1):
vp1 = ka�zi-d,j-d + kb�zi,j-d + kc�zi-d,j + kd�zi,j – zp1
For points placed in the second mesh (2):
Vp2 = ka�zi,j-d + kb�zi+d,j-d + kc�zi,j + kd�zi+d,j – zp2
For points placed in the third mesh (3):
Vp3 = ka�zi-d,j + kb�zi,j + kc�zi-d,j+d + kd�zi,j+d – zp3
For points placed in the fourth mesh (4):
Vp4 = ka�zi,j + kb�zi+d,j + kc�zi,j+d + kd�zi+d,j+d – zp4
As can be seen from figure 2.13 The weights functions according to the Match-T method:
� ka=(1-dx)(1-dy)/d 2
� kb=dx(1-dy)/d 2
� kc=(1-dx)dy/d 2
� kd=(dx dy)/d 2
where:
d
d
� dx=x(zs)-x(z(i,j))
� dy=y(zs)-y(z(i,j))
Z(i-d, j+d) Z(i, j+d) Z(i+d, j+d)
Z(i-d, j)
3 4
1
Z(i-d, j-d)
Z(i, j)
2
Z(i, j-d)
Z(i+d, j)
Z(i+d, j-d)
Figure 2.13: Determination of grid points for every mesh.
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