4.3.10.
Traverse
The menu item Calculate
> Traverse serves to calculate traverses on the basis of already
conducted surveys. This means that, prior to defining and calculating the
traverse, one must have registered the measurement values on all break points
and backsight points (see menu item 4.1.
Input).
With GART-2000®
CE a total of
four different kinds of traverses can be calculated, whereby the respective type
is automatically determined by the program:
1. Traverse linked on both sides: all four points PAR, PA, PE and PER must
be specified. GART-2000®
CE initially
calculates the longitudinal and transverse deviation. The calculation of
coordinates is carried out by means of transformation via both connecting
control points.
2. Closed-figure traverse (without orientation): only the points PA and PE need
to be specified. The traverse is calculated between the two connecting points.
3. Traverse linked on one
side: this only requires the first point PA and the first connecting control
point PAR to be specified. No closure error (misclosure) can be calculated with
this kind of traverse. All traverse points are ultimately attached one after the
other using polar measurements.
4. Ring traverse: the calculation of a ring traverse principally requires the
same input as a traverse linked on both sides. However, the starting and end
point (PA and PE) coincide. The calculation is carried out after the angular
closure error has been distributed evenly among the break points. The coordinate
inconsistencies are distributed in proportion to the distance.
Combined forms of
these four types of traverse can be calculated;
GART-2000®
CE
examines the plausibility of the values entered and produces a corresponding
error message if the traverse is not calculable.
The function Calculate > Traverse in
GART-2000® CE
opens up the relevant dialog window. This is where the control points are
entered, depending on the kind of traverse (PA, PAR, PE, PER). The points can be
selected by simply clicking them in the graphic or can be manually entered. The
abbreviations denote the following:
| Code | Point number of the starting point of the traverse |
| PAR | Point number of the connecting direction of the traverse |
| PE | Point number of the end point of the traverse |
| PER | Point number of the closing direction of the traverse |
The break points are entered with <Enter>. After this button has
been clicked, the point input dialog appears, where the break points must be
entered in the relevant order. If a point is to subsequently included, the
marker is placed at the relevant position in the list of break points and the
point is inserted in the list by clicking the button <Enter>. After
the input of points is completed, erroneous entries can be removed with <Delete>.
A new traverse can be defined with <New>.
Following definition of the traverse, it can be saved by clicking the button <Save>.
Via the button <Read> traverses saved in this way can be recalled
at a later stage. The calculation of the defined traverse is executed by
clicking the button <OK>.
In the output window that then opens up, the traverse type automatically
determined by GART-2000®
CE
is displayed, along with the number of break points and the total length
of the traverse.
The values FW, FL and FQ provide
information on the closure error that has been computed, which is also compared
with the official error/accuracy limits stipulated in Germany by the respective
state authorities.
The results of the calculation can be saved by clicking the button <Save>.
Via the button <Esc> the window can be closed without saving the
coordinates calculated. The measurement values from the traverse can optionally
be displayed by clicking the corresponding buttons.