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--- external:tectomt:tutorial [2009/01/21 11:26]
kravalova
+++ external:tectomt:tutorial [2009/01/21 12:01]
kravalova
@@ Line 8: / Line 8: @@
 TectoMT is a highly modular NLP (Natural Language Processing) software system implemented in Perl programming language under Linux. It is primarily aimed at Machine Translation, making use of the ideas and technology created during the Prague Dependency Treebank project. At the same time, it is also hoped to significantly facilitate and accelerate development of software solutions of many other NLP tasks, especially due to re-usability of the numerous integrated processing modules (called blocks), which are equipped with uniform object-oriented interfaces.
@@ Line 18: / Line 19: @@
   * Your system is Linux
   * Your shell is bash
-  * You have basic experience with bash and you can read basic Perl
+  * You have basic experience with bash and can read basic Perl
@@ Line 85: / Line 86: @@
 This tutorial itself has its blocks in ''libs/blocks/Tutorial'' and the application in ''applications/tutorial''.
@@ Line 96: / Line 101: @@
 {{ external:tectomt:pyramid.gif?300x190|MT pyramid in terms of PDT layers}}
-TectoMT blocks repository is saved in ''libs/blocks/''. In correspondence with ..., the blocks are located in directories describing their purpose.
+The notion of 'layer' has a combinatorial nature in TectoMT. It corresponds not only the layer of language description as used e.g. in the Prague Dependency Treebank, but it is also specific for a given language (e.g., possible values of morphological tags are typically different for different languages) and even for how the data on the given layer were created (whether by analysis from the lower layer or by synthesis/transfer).
 Thus, the set of TectoMT layers is a Cartesian product {S,T} x {English,Czech,...} x {W,M,P,A,T}, in which:
@@ Line 103: / Line 108: @@
   * {English,Czech...} represents the language in question
   * {W,M,P,A,T...} represents the layer of description in terms of PDT 2.0 (W - word layer, M - morphological layer, A - analytical layer, T - tectogrammatical layer) or extensions (P - phrase-structure layer).
+Blocks in block repository ''libs/blocks'' are located in directories indicating their purpose in machine translation.
 //Example//: Block adding Czech morphological tags (pos, case, gender, etc.) can be found in ''libs/blocks/SCzechW_to_SCzechM/Simple_tagger.pm''.
 There are also other directories for other purpose blocks, for example blocks which only print out some information go to ''libs/Print''. Our tutorial blocks are in ''libs/blocks/Tutorial''.
@@ Line 126: / Line 135: @@
 </code>
-Our plain text data ''sample.txt'' have been transformed into ''tmt'', an internal TectoMT format, and saved into ''sample.tmt''. Then, all four blocks have been loaded and our data has been processed. We can now examine ''sample.tmt'' using a regular text editor. We'll now stop and describe data structure in TectoMT.
+Our plain text data ''sample.txt'' have been transformed into ''tmt'', an internal TectoMT format, and saved into ''sample.tmt''. Then, all four blocks have been loaded and our data has been processed. We can now examine ''sample.tmt'' with a text editor (vi, emacs, etc).
   * One physical ''tmt'' file corresponds to one document.
@@ Line 347: / Line 356: @@
 ===== Your turn: more tasks =====
@@ Line 358: / Line 369: @@
 ==== SVO to SOV ====
-**Motivation**: During translation from an SVO based language (English) to an SOV based language (Korean) we might need to change the word order from SVO to SOV.
+**Motivation**: During translation from an SVO based language (e.g. English) to an SOV based language (e.g. Korean) we might need to change the word order from SVO to SOV.
 **Task**: Change the word order from SVO to SOV.
@@ Line 366: / Line 377: @@
   * To find an object to a verb, look for objects among effective children of a verb (''$child<nowiki>-></nowiki>get_attr('afun') eq 'Obj' ''). That implies working on analytical layer.
   * For debugging, a method returning surface word order of a node is useful: ''$node<nowiki>-></nowiki>get_attr('ord')''. It can be used to print out nodes sorted by attribute ''ord''.
-  * Once you have node ''$object'' and node ''$verb'', use method ''$object<nowiki>-></nowiki>shift_before_node($verb)''. This method takes the whole subtree under node ''$object'' and counts the attributes ''ord'' (surface word order) so that all nodes in subtree under ''$object'' have smaller ''ord'' than ''$verb''. That is, the method rearranges the surface word order from VO to OV.
+  * Once you have node ''$object'' and node ''$verb'', use method ''$object<nowiki>-></nowiki>shift_before_node($verb)''. This method takes the whole subtree under node ''$object'' and re-counts the attributes ''ord'' (surface word order) so that all nodes in subtree under ''$object'' have smaller ''ord'' than ''$verb''. That is, the method rearranges the surface word order from VO to OV.
@@ Line 396: / Line 410: @@
 ==== Prepositions ====
-{{ external:tectomt:preps.png?200x80|}}
+{{ external:tectomt:preps.png?200x80|Prepositions example}}
 **Motivation**: In dependency approach a question "where to hang prepositions" arises. In praguian style (PDT), prepositions are heads of the subtree and the noun/pronoun is dependent on the preposition. However, another ordering might be preferable: The noun/pronoun might be the head of subtree, while the preposition would take the role of a modifier.
@@ Line 405: / Line 419: @@
 You are going to need these new methods:
-  * ''my @children = $node<nowiki>-></nowiki>get_children''
+  * ''my @children = $node<nowiki>-></nowiki>get_children()''
-  * ''my $parent = $node<nowiki>-></nowiki>get_parent''
+  * ''my $parent = $node<nowiki>-></nowiki>get_parent()''
   * ''$node<nowiki>-></nowiki>set_parent($parent)''
 //Hint//:
   * On analytical layer, you can use this test to recognize prepositions: ''$node<nowiki>-></nowiki>get_attr('afun') eq 'AuxP' ''
-  * You can use block template in ''libs/blocks/BlockTemplate.pm''. To see the results, you can again use TrEd (''tmttred sample.tmt'')
+  * You can use block template in ''libs/blocks/BlockTemplate.pm''.
+  * To see the results, you can again use TrEd (''tmttred sample.tmt'')

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