LOCUS produces two output files, *.adj and *.ph1, both in ASCII text format. Note that these files may not appear correctly formatted if opened using Microsoft Notepad, but will appear correct using other text editors (e.g., WordPad, TextPad, etc.). These files are named the same as the .hgz file the user uploaded and are compressed and available in “userfile”.zip. Userfile.adj is the complete adjustment report. Userfile.ph1, which NGS calls the “phase one”, has unadjusted heights and other information. The section of the .adj file with adjusted geopotential numbers and orthometric heights (elevations) is displayed on the screen after LOCUS has run. The main sections of the output files are briefly described below.
"Userfile".adj. This is the main output file users will refer to. The input file name, datum, and constraints are shown as the user selected them when setting up the LOCUS run.
The following test values of the statistics, if exceeded, cause an asterisk (*) to be written in the Adjustment statistics section later in the report:
38:Flag Norm 2.50 39:Flag V 5.00 (mm)
Adjusted values (example below): 1. Geopotential (geopotential numbers, units of kgal-m) These quantities are determined from input orthometric heights and gravity values, then adjusted. 2. Elevation (Orthometric heights, units of m). These quantities are derived from the adjusted geopotential numbers using the gravity values. Differences between these adjusted heights can be compared against differences between heights published on NGS datasheets for evaluating a two- or three-mark tie.
Line/Part: L26771 SSN*: mark constrained Mark ID SSN PID Designation Geopotential Elevation Codes 0 1037* QP0857 2180 J 406.77434 414.82070 (m) 1 1036 QP0858 2180 H 419.64711 427.94752 2 1001* QP0862 2180 G 404.89534 412.90390 3 1002 DG9889 URNESS 402.92006 410.88937
Adjustment statistics (example below): Any residual value over 5 mm in this section has an asterisk (*) which indicates an observation that does not fit as expected and / or a mark that may have moved. The Norm (normalized residual) column (farther to the right, not shown here) is an additional statistical indicator which, if flagged by *, indicates potential problems with the new observations, the existing network, or both.
Mark IDs from to Geopotential Sigma Residual Stats from to Line/Part SSN SSN Runs km Year OC Difference Prior Post V Norm 2 3 L26771 1001* 1002 2 1.01 2005 21 -1.97799 1.5 0.9 14.91* 10.40* 3 4 L26771 1002 1004* 2 0.62 2005 21 9.70967 1.1 0.9 9.19* 8.17* ----------------------------------------------------------------
"Userfile".ph1: “phase one” file, displays the starting height, positions, distances along the line, spur lines, and observed heights with corrections applied (all those available, except the orthometric correction). Differences between the phase one observed heights can be compared against field differences from older surveys of the same marks.