Geography Reference
In-Depth Information
parameters as well as ellipsoidal form parameters. In contrast, J 23 includes the relevant 2
×
3
submatrix ( l, b ) /∂ ( x, y, z ) at the Taylor point of the general 3
3 matrix ( l,b,h ) /∂ ( x, y, z ).
Indeed, the complicated derivative matrix ( l, b, h ) /∂ ( x, y, z ) is computed from its simple
inverse ( x, y, z ) /∂ ( l,b,h ). Equation ( 21.28 ) is the closed form representation of the Jacobi matrix
A given as a function of
×
{
L, B, H
}
of the global curvilinear coordinate system!
Box 21.3 (Curvilinear coordinate conformal transformation (datum transformation) extended
by ellipsoid parameters, ellipsoid-of-revolution
E
A 1 ,A 2
versus
E
a 1 ,a 2
, ellipsoidal coordinates
{
l,b,h
}
of local type versus ellipsoidal coordinates
{
L, B, H
}
of global type).
+ semi-major axes; E := ( A 1
Λ 2 ) /A 1 , e = ( α 1
A 1 ,a 1 R
a 2 ) /a 1 relative
eccentricities.
Direct transformation
{
l,b,h
} →{
x, y, z
}
:
x =
+ h ( l,b ) cos b cos l =[ n ( b )+ h ( l,b )] cos b cos l,
a 1
1
e 2 sin 2 b
y =
+ h ( l,b ) cos b sin l =[ n ( b )+ h ( l,b )] cos b sin l,
a 1
1
e 2 sin 2 b
(21.13)
z = a 1 (1 e 2 )
+ h ( l,b ) sin b
=[(1 − e 2 ) n ( b )+ h ( l,b )] sin b,
1
e 2 sin 2 b
e 2 )
a 1
a 1 (1
1
(1
n ( b ):=
, m ( b ):=
e 2 sin 2 b ) 3 .
(21.14)
e 2 sin 2 b
Direct transformation {L, B, H} →{X,Y,Z} :
X =
+ H ( L, B ) cos B sin L
A 1
1 − E 2 sin 2 B
=[ N ( B )+ H ( L, B )] cos B sin L,
Y =
+ H ( L, B ) cos B sin L
A 1
1
E 2 sin 2 B
=[ N ( B )+ H ( L, B )] cos B sin L, l
(21.15)
Z = A 1 (1
+ H ( L, B ) sin B
E 2 )
1
E 2 sin 2 B
E 2 ) N ( B )+ H ( L, B )] sin B,
=[(1
 
Search WWH ::




Custom Search