The Adjust File page allows you to perform an adjustment directly from the contents of a data file. For users who prefer to set up and define all adjustment parameters within a data file, this is a compelling option.
Network design works when the quality obtained in the field is as good or better than what you designed.
You can either perform an Adjustment of existing field data (the most common scenario) or evaluate the Design (Pre-Analysis) of a network that has not yet been measured.
Network design allows you to determine the statistical results you can obtain in the field—before you even make a measurement. By working with three variables, you can design a network that will help you minimize field costs, while achieving the quality standards specified for the project.
The three variables are:
As you can see, the data entry for Adjustment vs. Design is nearly identical. However, Design cannot compute the approximate coordinates, since you have provided no real observation values. Therefore, you must provide the approximate coordinates for each station (in 1D, 2D, or 3D, depending on the network type).
When you select an project file, all the usual network adjustment statistics will be computed for your review. These statistics are a function of the location of the stations (approx coords), the observation types used and the expected error of the observations. If the resulting statistics (distance errors, ALTA results, 2D error ellipses, etc.) don’t meet the project requirements, keep tweaking your design until they do.
For example, you may do one or more of the following to improve your design results:
Later, when you do the field work, if you set your stations at the designed locations, measure the designed observations and achieve the quality of the designed standard deviations, you are guaranteed to get a final adjustment that meets your project quality requirements (after removing any blundered observations).
Note: When using the Adjust by File feature (adjusting from a file), insert the following keyword near the top of the input file to indicate you are performing Network Design and not a Network Adjustment.
There are several example network files available on our website, found on the Sample Network Files page. Below is a complete input file for a Leveling Network. It is ready to load and run within the Adjust File page:
_UNITS; M; D
! Weight the network by the distance between points (in km, miles, etc.)
! Defines the fixed height station, its elevation and standard deviation
_STA_COORD; BOON; 0; 0; 100.0; 0; 0; 0; 0; 0; 0.02; 0; 0; 0; 0; 0
_OBS_HGTDIFF; BOON; COOP; 2.56916; 25.0
_OBS_HGTDIFF; BOON; GONE; -0.44714; 14.0
_OBS_HGTDIFF; COOP; DEED; 5.09749; 36.0
_OBS_HGTDIFF; COOP; FARGO; -1.98974; 49.0
_OBS_HGTDIFF; DEED; ECHO; -3.82921; 27.0
_OBS_HGTDIFF; ECHO; FARGO; -3.26777; 41.0
_OBS_HGTDIFF; FARGO; GONE; -1.02169; 17.0