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Chapter 6
Advanced use of graphs
6.1 Types of graphs
Unitex can work with four types of graphs that correspond to the following uses: automatic inflection of dictionaries, preprocessing of texts, normalization of text automatons
and search for patterns. These different types of graphs are not interpreted in the same way
by Unitex. Certain operations like the transduction are allowed for some types and forbidden for others. In addition, the special symbols are not the same depending on the type of
the graph. This section presents each type of graph and shows their peculiarities.
6.1.1 Inflection graphs
An inflection graph describes the morphological variation that is associated with a word
class by assigning inflectional codes to each variant. The paths of such a graph describe the
modification that have to be applied to the canonical forms so that the transduction contain
the inflectional information that will be produced.
Figure 6.1: Example of an inflectional grammar
The paths may contain operators and letters. The possible operators are represented by
the characters L and R. All letters that are not operators are characters. The only allowed spe-
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