This attribute specifies the geodetic
latitude of the observer, in degrees, relative to the IAU 1976 reference ellipsoid. The basic
Frame
class makes no use of this attribute, but specialised subclasses of Frame may use it. For
instance, the
SpecFrame,
SkyFrame and
TimeFrame classes use it. The default value is
zero.
The value is stored internally in radians, but is converted to and from a degrees string
for access. Some example input formats are: "
22:19:23.2"
, "
22 19 23.2"
, "
22:19.387"
, "
22.32311"
, "
N22.32311"
, "
-45.6"
, "
S45.6"
. As indicated, the sign of the latitude
can optionally be indicated using characters "
N"
and "
S"
in place of the usual "
+"
and "
-"
. When converting the stored value to a string, the format "
[s]dd:mm:ss.ss"
is used, when "
[s]"
is "
N"
or "
S"
.
Frame
All Frames have this attribute.
SpecFrame
Together with the
ObsLon,
Epoch,
RefRA and
RefDec attributes, it defines the Doppler shift
introduced by the observers diurnal motion around the earths axis, which is needed when converting
to or from the topocentric standard of rest. The maximum velocity error which can be caused by an
incorrect value is 0.5 km/s. The default value for the attribute is zero.
TimeFrame
Together with the
ObsLon attribute, it is used when converting between certain time scales (TDB, TCB, LMST, LAST)