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routines of a special eartographic libra- 
ry. In the table nr.l are given transfor- 
mation parameters for one 1:25,00C scale 
topographic map sheet 
  
  
  
Table no,l 
Transformation 
Parameters Linear Affine| Projec 
conformal tive 
No.of points 4 4 6 
The unit weight 
tolerance 1.125 0,980 [0.920 
Maximum location 
error (m) 1.5 1.4 1.2 
  
  
  
  
From that test results the conclusion 
that in an automated mapping system must 
use all three transformations, the selec- 
tion of one of them being the user's 
choice, 
3. TOLBRANCES IN DIGITAL MAPPING 
In digital mapping one uses planimetric 
tolerances like the map resolution tole- 
rance,topology build tolerance,the match 
tolerance, weed tolerance etc,,and height 
tolerance. 
3.1. Map resolution tolerance 
In $1 resulted the map resolution of 
coordinates 1.7 m for 1:25,000 scale topo- 
graphic map (0.7 mm on the map sheet). 
Considering the tolerance value 3 times 
bigger, results the value 0.2 mm on the 
map. 
In the graph theory sense, the map reso- 
lution tolerance may be defined like the 
threshold value of a distance between two 
end-points of the arc (nodes). As a rule, 
this tolerance is used to join the arcs 
in one node (ESRI,1989). 
3.2. Topology build tolerances 
Topology build tolerances are dangle 
lenght and node match tolerance. The dang- 
le lenght is the minimum lenght allowed for 
dangling arcs.Any dangling arc less than 
this value of the tolerance is deleted. 
The node match tolerance is the minimum 
distance between nodes. All the nodes wi- 
thin the node match tolerance of each 
other are snapped together. As a rule,the 
dangle lenght and the node match toleran- 
ce have the same value. 
3.3. Weed tolerance 
The weed tolerance is used for the decre- 
asing of the number of points of a linear 
feature in esrtographic meaning or of an 
arc in topological meaning, especiely in 
cartographic generalization. 
3.4. Tic registration tolerance and tic 
match tolerance 
Considering the case with redundance,the 
RMS error Gj is calculated automaticaly, 
O9 =L2(V24V2 17 C2n-k911/2 (4) 
where n is the number of tics (with the 
coordinates in both systems), k is the 
number of parameters and Vt and V_ are 
the residuals. J 
The tolerance is t times bigger than the 
RMS error, when t is determined with the 
Student distribution (table no.2). 
  
  
Table no.2 
Transformation N IK | 9n-k | t(p=0.22) 
Linear-conformal 414 4 2.110 
Affine 616 6 2.447 
Projective 618 4 2.776 
  
  
  
  
  
The accurate digitizing will give the low 
RMS error. If the fuzzi tolerance is 0.07 
mm (on the map sheet), the digitizing ac- 
curácy must be 0,025-0,031 mm, One can 
determine the match tolerance depending 
on the acceptable error described in 
national mapping standards. 
3.5, The height tolerance 
For the &ccuracy studies of DTM,from 
practice and theory the function of the 
terrain surface (Kubik,1988) is 
ta) = xa* (5) 
where d is the distance between points,R 
is the terrain rugozity, V(d) is the vari- 
ance of the height, with the value k for 
à = 1. The height tolerance T is 
T= ag A, 2 Ju: (6) 
6 (R+1)(R+2) 
where t is the Student distribution 
factor : 
4, ACKNOWLEDGEMENTS 
The planimetric and altimetric digital 
mapping tolerances have a remarcable impor- 
tance in data capture and in data proce- 
ssing. The concrete values deter mina- 
tion requires additional studies, in the 
same time with the computer algorithms 
programming and the automated tehnologies 
design. 
5. REFERENCES 
ESRI,1989.ARC/INFO Users Guide.Vol.Il,pp. 
10,18-10.26. 
Jeypalan,kK.,1972.Calibration of a com- 
parator.Photogramm.Eng.,38(5) 1472-478. 
Kratky,V.,1972. Image transformations. 
Photogramm.Eng.38(5):463-471. 
Kubik,K.,1988.Digital elevations models: 
review and outlook. In: Int.Arch.Photo- 
gramm.Remote Sensing. ,Kyoto-Japan, Vol. 
27,Part.B3,pp.415-426. 
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