1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
|
.help obs Jun99 "Slalib Package"
.nf
SUBROUTINE slOBS (N, C, NAME, W, P, H)
- - - -
O B S
- - - -
Parameters of selected groundbased observing stations
Given:
N int number specifying observing station
Either given or returned
C c*(*) identifier specifying observing station
Returned:
NAME c*(*) name of specified observing station
W dp longitude (radians, West +ve)
P dp geodetic latitude (radians, North +ve)
H dp height above sea level (metres)
Notes:
Station identifiers C may be up to 10 characters long,
and station names NAME may be up to 40 characters long.
C and N are alternative ways of specifying the observing
station. The C option, which is the most generally useful,
may be selected by specifying an N value of zero or less.
If N is 1 or more, the parameters of the Nth station
in the currently supported list are interrogated, and
the station identifier C is returned as well as NAME, W,
P and H.
If the station parameters are not available, either because
the station identifier C is not recognized, or because an
N value greater than the number of stations supported is
given, a name of '?' is returned and C, W, P and H are left
in their current states.
Programs can obtain a list of all currently supported
stations by calling the routine repeatedly, with N=1,2,3...
When NAME='?' is seen, the list of stations has been
exhausted.
Station numbers, identifiers, names and other details are
subject to change and should not be hardwired into
application programs.
All station identifiers C are uppercase only; lowercase
characters must be converted to uppercase by the calling
program. The station names returned may contain both upper-
and lowercase. All characters up to the first space are
checked; thus an abbreviated ID will return the parameters
for the first station in the list which matches the
abbreviation supplied, and no station in the list will ever
contain embedded spaces. C must not have leading spaces.
IMPORTANT -- BEWARE OF THE LONGITUDE SIGN CONVENTION. The
longitude returned by slOBS is west-positive in accordance
with astronomical usage. However, this sign convention is
left-handed and is the opposite of the one used by geographers;
elsewhere in SLALIB the preferable east-positive convention is
used. In particular, note that for use in slAOP, slAOPA
and slOAP the sign of the longitude must be reversed.
Users are urged to inform the author of any improvements
they would like to see made. For example:
typographical corrections
more accurate parameters
better station identifiers or names
additional stations
P.T.Wallace Starlink 21 April 1999
Copyright (C) 1999 Rutherford Appleton Laboratory
Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
.fi
.endhelp
|
