N
e could
nnected
ion 2.1)
ent ver-
1).
1e of the
: for bi-
1es, etc.
j)
to each
hm you
nple for
can be
ls to do
0 assign
; known
ne from
orithms
or directly from the human being in charge of the
computation.
If the complexity of the situation so requires or if
one is trying to detect structural gross errors, the
above procedure could be done even interactively.
8 CONCLUSIONS AND OUTLOOK
From Section 3, Section 4 and from [3] it seems pos-
sible to set up a discrete model for the classical [least
squares] adjustment of general networks. All the in-
formation required for the model is contained in the
hypergraph associated to the functional model design
hypermatrix (block matrix). In particular, operations
like formation of reduced normal equations, formation
of nested dissection blocks and partial elimination of
unknown groups can be formulated as pure [general-
ized] numbering/elimination operations on graphs.
It is quite clear that for some of the concepts
and the results presented here to become practica-
ble (recall Section 6.4) key problems are still to be
solved; considerable research is still to be done both
in the theoretical and applied sides. This is, there-
fore, just an intermediate paper though some of its
ideas have been already applied at the Institut Car-
tografic de Catalunya in the development of the Geo-
TeX system [4]. (More details, practical motivation
and proofs to all statements made here can be found
in [3].)
Last but not least, it will be more than enough if
the paper contributes to the growing feeling that tech-
niques from discrete mathematics can be of help for
a new generation of photogrammetric/geodetic proce-
dures and software, even in the almost old-fashioned
field of network adjustment.
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Ph.D. dissertation, Departament de Matematica
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[4] Colomina,l.,Navarro,J.A.,Térmens,A.,1992.
GeoTeX: a general point determination system.
In: International Archives of Photogrammetry,
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[8
——À
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