STAR*NET V6 - Circe

Example 6:
Chapter 5 Preparing Input Data
C A106 1978.23 1844.76 965.2 0.023 0.03 0.095
Station “A106” has given coordinates, each with an entered standard error. These
standard error values cause the coordinates to be neither completely free nor completely
fixed. These values may be standard deviation values computed from some previous
adjustment, and represent the strength of the coordinates in this adjustment. Therefore
these coordinates will be considered as observations in the adjustment.
The “P” Code: Geodetic Positions for a Station (Grid Jobs Only)
Format for 2D data:
P Station Latitude Longitude [Std Errors]
Format for 3D data:
P Station Latitude Longitude Elev [Std Errors]
When preparing data for grid a job (NAD27, NAD83, UTM, Custom, etc.) you may enter
a Geodetic Position for any station rather than a grid coordinate. The order of data
entered on a “P” line is always latitude followed by longitude and is not affected by the
“NE” or “EN” order specified in the project options for coordinates.
Standard errors entered, however, are not angular standard errors for the Latitude and
Longitude values, they are the standard errors for the corresponding North and East
values calculated from the positions. Therefore on a “P” line, the order of the standard
errors is always in NE order to correspond to the latitude and longitude entries and is not
affected by the order specified for coordinates in the project options.
Since STAR*NET uses a coordinate-based system, any entered latitude and longitudes
are internally converted to grid coordinates during processing, and the program then
adjusts the job just as if these coordinates had been entered in the first place. Any
“partially” fixed latitude or longitude entered with a north or east standard error will be
handled as a coordinate observation. It will be counted in the statistics and will show up
as an observation in the “Adjusted Observations and Residuals” section of the output
listing file.
The “Longitude Sign Convention” selected in the project options must be followed when
when entering geodetic positions data. See page 19 for details on this option setting. You
can to use positive west longitudes” (as preferred in the United States and Canada), or
negative west longitudes (as preferred by the international community). Whichever
option preference is selected, that convention controls the interpretation of signs of
longitudes for all grid systems, NAD27/83, UTM and Custom!
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