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define the degree of approximation in the results visualization 
(number of digits) and to enter three different procedures. 
Particularly: 
1) "LIVELLAZIONE" is the main procedure allowing to 
input, to edit, to analyze, to elaborate and to export the 
measures; 
2) "QUOTE APPROSSIMATE" is a secondary procedure that 
can import height differences and calculate the approximate 
elevation of the benchmarks according to a previously fixed 
one; 
3) "UTILITÀ"' is an additional utility procedure able to read, 
to edit, to perform single or clustered operations on the data. 
The interface of the procedure "LIVELLAZIONE" has been 
planned in such a way as to hold under visual control all the 
data (zone "Input"), all the results (zone "Output"), all the 
editing functions (zone "Editing") and the more used commands 
(ex.: "CALCOLA"). On the contrary, the operations to be 
executed with less frequency, are selectable through the menus 
(Fig. 2). 
The measures can be introduced manually or imported by 
ASCII file, structured in an appropriate way. The presentation 
of these values is earned out on a grid, every line of which 
constitutes a record and the columns contain the following 
fields: 
• station name; 
• back point name; 
• reading to the levelling staff on the left graduation for the 
back point (in m); 
• reading to the levelling staff on the right graduation for the 
back point (in m); 
• forward point name; 
• reading to the levelling staff on the left graduation for the 
forward point (in m); 
• reading to the levelling staff on the right graduation for the 
forward point (in m); 
• distance between back point and forward point (in km). 
The calculation provides a series of results that appears on a 
special grid in the "Output” zone. The data can be saved and 
imported from an ASCII file structured in an appropriate way. 
The calculated values being numerous, a legend has been 
prepared to help the reading on a video through special buttons. 
Particularly in the output zone there have been introduced the 
following fields: 
For every station: 
• station name; 
• back point name; 
• forward point name; 
• average difference between left readings and right readings 
(mm); 
• difference of the left readings (in m); 
• difference of the right readings (in m); 
• difference between left and right readings on the back 
point (in m); 
• difference between left and right readings on the forward 
point (in m); 
• out tolerance indicator of the levelling staff constant for the 
back point; 
• out tolerance indicator of the levelling staff constant for the 
forward point. 
For everv r section in going; 
• section name; 
• section height difference in going (in m). 
For every section in return: 
• section name; 
• section height difference in return (in m); 
• average difference of the section between going and return 
(in m); 
• section length (in km); 
• closing error between going and return (in mm); 
• tolerance (in mm); 
• out tolerance indicator of the closing error of the section. 
For every ring: 
• ring name; 
• total difference in going (in m); 
• total difference in return (in m); 
• ring length (in km); 
• closing error ring (in mm); 
• tolerance (in mm); 
• out tolerance indicator of the closing error of the ring. 
In practice at first, the calculation evaluates, either for the 
forward point or for the back point, the differences between left 
reading and right reading to the levelling staff and compares the 
result with the admissibility range of the levelling staff constant, 
pointing out gross errors in a special column. Then it calculates 
the difference between the right readings and that between the 
left ones. Finally the average is calculated between the last 
values. 
When the procedure recognizes the end of the section in going, 
it calculates the stun of all the average difference of going and 
introduces it as a section difference in going. 
If, instead, the section end in return is recognized, the procedure 
performs the calculation of the sum of all the average gradients 
of return and introduces it as a section difference in return, then 
calculates the average between differences in going and 
differences in return and the difference between the two 
(closing error), besides it calculates the section length and then 
the tolerance given by the length multiplied for the constant 
given in the special box, signals finally in the last column if the 
error of closing overcomes tolerance. 
When, instead, the end ring is recognized, the average gradients 
sum of going, the average gradients sum of return and the 
closing error on the ring is produced, then the length of the ring 
and therefore the tolerance, if the closing error overcomes 
tolerance a signal appears in the special column. 
Finally, all the results are reanalyzed and, in an area 
denominated "Analysis of the Results", the maximum removals 
from the levelling staff constant and from the tolerance appear. 
Such fields appear underlined in red if they overcome the 
admissible values. Then, when both boxes introduce numbers in 
black we understand that the calculation is completely in the 
limits of acceptability. 
Besides the normal procedures of opening, closing and saving 
files (independent on the data and on the results), it is possible 
to stamp some printouts, to export files of gradients, to export 
files usable as an input for the least squares adjustment, to set 
the admissibility range for the levelling staff constant and to 
define the moltiplicative constant for the tolerance on the 
closing errors. 
Besides the presence of two help windows, one reserved to the 
software usage and the other to the files structuration, facilitates 
the procedure usage. 
The editing has been predisposed in such a way as to favour the 
realization of the more frequent operations, in fact, either the 
data or the results can be modified interactively through the 
following operations: 
• editing or insertion of a single value;