STAR*NET V6 - Circe

Point Descriptors
Chapter 5 Preparing Input Data
A point descriptor, if entered, is always the last item on a data line. A descriptor may be
assigned to any station. A descriptor is prefixed by a single or double quote character and
can be up to 48 characters in length. Descriptors can be entered on Coordinate or
Elevation data lines, Geodetic Positions data lines, or any kind of observation data line.
For Traverse lines, the descriptor is assigned to the “AT” station name. For all other
kinds of observation lines, the descriptor is assigned to the “TO” station name. Once a
descriptor has been assigned to a network station, any subsequent descriptor entered for
the same station will be ignored. Point descriptors are written to the output coordinate
file as well as the listing file. Examples:
C 4 5644.445 6645.526 ! ! 'Jones & Taylor
M 2-1-6 38-24-76 963.672 'Descriptor for Sta6
D 2-7 2044.334 'Descriptor for Sta7
Providing Approximate Coordinates
For a least squares adjustment to work, approximate coordinates (and elevations if you
are running a 3D adjustment) must exist for all adjustable stations in a network.
Fortunately, STAR*NET has the ability to look through your data and figure out the
approximate coordinates and elevations based on the actual angle, distance and vertical
observations present in the data file. They are automatically computed using a variety of
methods including angle-angle intersection, and angle-distance computation.
Often, however, you will have to enter approximate coordinates for a station or two to
help STAR*NET get started calculating other approximate coordinates. For example, in
the first sample project in the tutorial, we gave approximate coordinates for the first
traverse backsight point. STAR*NET will tell you when it can’t compute coordinates by
posting a message in the error file.
When a network has a full compliment of entered angles and distances, simply providing
fixed or approximate coordinates for some station directly adjacent to another station
having known coordinates (or supplying a fixed or approximate bearing or azimuth
adjacent to another station in the network having known coordinates) is normally all that
is required to allow STAR*NET to complete the job of computing the remaining
approximate coordinates.
Some networks will require you to provide coordinates for many or all of the stations. In
the case of a pure trilateration project (distances only) for example, you would have to
supply approximate coordinates for all points since STAR*NET is not be able to
determine coordinates from distances alone.
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