Geoscience Reference
In-Depth Information
Fig. 5.9 The meridian that
contains point P
Z
X 2
tan B 0
p
:
Y 2
þ
tanB 1 ; the
iterations can be repeated until the difference between the two values of B is less
than 0.0001 00 or the difference between the adjacent values of tan B is less than
5
The tanB on the left side (tanB 1 ) can be computed. Set tanB
10 10 .
From Fig. 5.9 , in the right triangle PK p P 3 , it is apparent that:
p
X 2
Y 2
þ
cos B
H :
N
þ
Hence, we get:
p
X 2
Y 2
þ
H
cos B
N
:
ð
5
:
22
Þ
Equations ( 5.20 ), ( 5.21 ), and ( 5.22 ) are the expressions for computing L, B, and
H with X, Y, and Z.
Such transformation can be easily understood. The problem is that ( 5.21 ) needs
iteration. There are many closed formulae for transformation between L, B, H, and
X, Y, Z (see Featherstone and Claessens 2008; Vermeille 2004).
An example of transformation between L, B, H and X, Y, Z is shown in Table 5.1 .
Search WWH ::




Custom Search