[evlatests] AG745 target position

[Ken Sowinski]

On Fri, 13 Jul 2007, Scheduling Officer wrote:

> During two observations in June, I fast-switched to an offset target
> position of
>   RA(J2000) = 12 40 35.8100   Dec(J2000) = -00 29 16.400
>
> An AIPS scan listing of a Modcomp-based observation on June 18 says
> the target position is
>   RA(J2000) = 12 40 35.8101   Dec(J2000) = -00 29 16.401
>
> An AIPS scan listing of a Modcomp-free observation on June 30 says
> the target position is
>   RA(J2000) = 12 40 35.8100   Dec(J2000) = -00 29 16.400
>
> Why the ending 1's on the Modcomp-based observation?  - Joan

The old system represented the difference between the primary
and secondary positions as a float and adjusted the RA and DEC
for each pointing rather than remembering the two.  Depending
on the magnitude of the difference between the two positions
a float did not always have enough precision.  The new system
is more correct.