! Columbus supports keywords that allow you to scale standard deviations for each
! observation type. When one of the following keywords is encountered, the
! observation standard deviation it applies to is scaled on Import or when
! using Adjust From File.
! Example:
! Scale all the standard deviations for chord distances by 1.5 when they are loaded from
! the file.
_S_CHORD_SD; 1.5
! This will apply to any chord distances that are below (this keyword) in the file.
! Turn the scaling off (for all chord distances that follow), set _S_CHORD_SD to 1.0.
_S_CHORD_SD; 1.0
! NOTE:
! Some scalars are actually applied to the observation set covariance matrix (not the
! standard deviation). Applying a scalar to a covariance matrix is different than applying a
! scalar to a standard deviation.
! If you apply a scalar of 2.0 to a covariance matrix, that is equivalent to applying a scalar
! or 1.4142 to a standard deviation.
! The easiest way to apply the same scalar to all observations is to use the keyword
_ADJUST_APRIORI_FACTOR. This is applied at adjust time (not during import or file loading).
! Following is how to apply the equivalent scalar to a GPS covariance matrix and to chord distance
! standard deviation:
! Example 1:
! Desired covariance scalar is 4.0
_S_XYZ_COV; 4.0
! Now the square root of 4.0 is 2.0, so use that for the standard deviation scalar.
_S_CHORD_SD; 2.0
! Example 2:
! Desired standard deviation scalar is 3.0
_S_CHORD_SD; 3.0
! Now the square of 3.0 is 9.0, so use that for the covariance matrix scalar.
_S_XYZ_COV; 9.0
! Scale azimuth standard deviations when loaded from the file.
_S_AZ_SD; 1.3
! Scale direction standard deviations when loaded from the file.
_S_DIR_SD; 1.3
! Scale bearing standard deviations when loaded from the file.
_S_BEAR_SD; 1.3
! Scale horizontal angle standard deviations when loaded from the file.
_S_HA_SD; 1.3
! Scale zenith standard deviations when loaded from the file.
_S_ZEN_SD; 1.3
! Scale chord (slope distance) standard deviations when loaded from the file.
_S_CHORD_SD; 1.5
! Scale horizontal distance standard deviations when loaded from the file.
_S_HOR_DIST_SD; 1.5
! Scale height difference standard deviations when loaded from the file.
_S_HGTDIFF_SD; 1.5
! Scale delta north standard deviations when loaded from the file.
_S_DN_SD; 1.5
! Scale delta east standard deviations when loaded from the file.
_S_DE_SD; 1.5
! Scale delta up deviations when loaded from the file.
_S_DUP_SD; 1.5
! Scale geodesic azimuth standard deviations when loaded from the file.
_S_GEODESIC_AZ_SD; 1.7
! Scale geodesic distance standard deviations when loaded from the file.
_S_GEODESIC_SD; 1.7
! Scale latitude standard deviations when loaded from the file. Only applies
! to latitude coords defined using the _OBS_LAT keyword.
_S_LAT_SD; 2.5
! Scale longitude standard deviations when loaded from the file. Only applies
! to longitude coords defined using the _OBS_LON keyword.
_S_LON_SD; 2.5
! Scale height standard deviations when loaded from the file. Only applies
! to hgt coords defined using the _OBS_HGT keyword.
_S_HGT_SD; 2.5
! Scale north standard deviations when loaded from the file. Only applies
! to north coords defined using the _OBS_NORTH keyword.
_S_NORTH_SD; 2.5
! Scale east standard deviations when loaded from the file. Only applies
! to east coords defined using the _OBS_EAST keyword.
_S_EAST_SD; 2.5
! Scale GPS covariance matrix when loaded from the file.
_S_XYZ_COV; 2.0
! Scale lat, lon, hgt covariance matrix when loaded from the file.
_S_LLH_COV; 2.0
! Scale north, east, hgt covariance matrix when loaded from the file.
_S_NEH_COV; 2.0