The GraphViewer is used to browse through the whole corpus (corpus exploration) or to browse through the matching corpus graphs (match visualization). The corpus exploration mode is activated by pressing the Explore corpus button or selecting the Explore item in the Corpus menu. The match visualization is automatically activated after query processing. When opened, the GraphViewer will display the first corpus graph or the first matching corpus graph, respectively.
Please note: You can easily switch between the TIGERSearch main window and the GraphViewer
window using the shortcut buttons in the lower left corner of both windows. If you press
a shortcut button, the corresponding window will be moved in front of all other windows on your desktop.
The tokens of the currently displayed corpus graph is presented at the bottom of the window. You can navigate through the matching corpus graphs by using the navigation panel at the bottom of the GraphViewer. You can either view them one by one in the order they have been found using the Previous and Next buttons, or browse through the corpus graphs using the slider above these buttons.
Figure: Browsing through the (matching) corpus graphs
You can move right to the last graph by pressing the Last button and back to the first one pressing the First button. You may also move to a graph with a certain position within the results. Just type in the position number in the input field between the First and Last button and press Return.
If there are two or more matching subgraphs in the same corpus graph, the green navigation arrows in the Subgraph box on the right hand side of the navigation bar will be activated. Now you can navigate from one matching subgraph to the next using the green buttons. In the example screenshot, there are four NP subgraphs within the current corpus graph matching the query [cat="NP"].
The information box on the left shows the total number of matching corpus graphs and the total number of matching subgraphs within all corpus graphs. Thus, we have 176 corpus graphs which comprise at least one NP and 448 NPs in the whole corpus.
Focus on match
If you do not want to see the whole graph, but only the matching subgraph, you can turn on the Focus on match button in the toolbar (represented as a flash light turned on/off). The GraphViewer will display just the matching subgraph. Turning off the Focus on match button will display the initial view of the graph.
Please note: The Focus on match feature is not accessible in the corpus
exploration mode.
Figure: Focussing the matching structure
Sentence text field
If you do not want to see the tokens of the graph you can turn off the Token button in the toolbar (represented by a T character turned on/off). Turning on the Token button will display the tokens again. To change the context size of the sentence text field (current sentence +- 0/1/2 context sentence(s)) you can use the display options menu.
Imploding subgraphs
If you want to hide parts of the graph you can implode subgraphs pressing the middle mouse button on the node which is the root of the subgraph you want to hide (cf. screenshot). If you are using a two-button mouse, clicking the left and right button simultaneously should emulate the middle button click. Clicking the imploded node again will expand it to original size. Of course, node imploding does not make sense for the root node and terminal nodes.
Figure: Imploding a subgraph
Node tooltip
If the mouse pointer is placed over a node (token or inner node), a node tooltip windows pops up. This windows comprises the annotation of all features:
Figure: Node tooltip
Refresh
If the graph is not displayed properly, use the Refresh button in the toolbar to repaint the graph.
If you are simultaneously working with the GraphViewer and the Statistical Viewer, you can easily switch between these two views using the shortcut icons in the lower left corner of both windows.
However, the two windows have also been designed to communicate with each other. The corpus graph currently displayed in the GraphViewer will be displayed and marked in the Statistical Viewer if you select the Display in Statistics item of the GraphViewer's context menu (activated by pressing the right mouse button in the GraphViewer panel).
Printing the current graph / Postscript export
You can print the current graph pressing the Print button. The print options can be selected in a platform-dependent print dialog. Some general options such as paper format can be specified in the page setup window which is activated by selecting the Pape Setup item in the Graph menu of the GraphViewer.
Please note: If you choose a Postscript printer in the print dialog (e.g. Apple Laserwriter),
you can use the Print into file option to create a Postscript version
of the displayed corpus graph. The created Postscript file may be used
by applications such as LaTeX. Please note that the quality of the
Postscript output depends on the selected printer and its parameters.
Exporting the current graph (image export)
You can save the current graph to several image formats (SVG, JPG, PNG, TIF, and PDF) using either the Export as image item of the context menu (activated by pressing the right mouse button), or the Export image icon (cf. picture icon) of the toolbar, or the Export image item in the Graph menu. A dialog window pops up, and you can select the options you prefer for saving the current graph (cf. screenshot).
Figure: Exporting the current corpus graph as an image
The export is based on the SVG format which is an XML-based vector graphics format. In contrast to binary formats such as JPG format, images encoded using SVG can be manipulated (e.g. scaled) without loss of quality. Thus, you can change a token or a syntactic category within the exported SVG file. If you selected an non-SVG image, first an SVG representation is generated and afterwards converted into the preferred format.
The SVG output has been designed in such a way that the different node types (inner/outer node, matching node, imploded node etc.) can be identified by additional XML attributes. Thus, this information can be used to modify the generated SVG image, e.g. by Cascading Stylesheets (CSS).
The image filters you can choose (cf. screenshot above) are realized by inserting predefined CSS stylesheets into the SVG document. In subsection 10.1 we explain how to add your own image filter to the SVG export.
Please note: Relative paths used to specify the export file are evaluated with regard to the
working directory.
Exporting the match forest (animated SVG image)
If you like other users to have a look at your favourite matches, you may want to export the matches in a format that does not depend on the TIGERSearch software suite. Of course, you might export all the matching corpus graphs as single images, but this solution would not be practical.
As an alternative, you can use the Export match forest option to export all matching corpus graphs to one single SVG file. The individual graphs are combined by SVG animations. Thus, you can use any SVG viewer to navigate through the match forest. Please note that the SVG viewer has to support SVG animations.
You can open the Match forest export window by pressing the Export match forest button (cf. forest icon) in the button toolbar or selecting the Export forest as SVG item in the Graph menu. Now you can specify the following parameters:
Figure: Exporting a match forest (animated SVG image)
Parameter: SVG file name
You can either generate an uncompressed SVG file (*.svg) or a compressed SVG file (*.svgz). Relative paths are evaluated with regard to the working directory. Compression reduces the size of the file to about 10% of its original size.
Parameter: match selection
You can restrict the export of all matching corpus graphs to a range of matching graphs, or specify them in a text field (e.g. 1-3;6-7). Note that you have to specify the number (or position) within the match forest, not the corpus graph ID.
Since a corpus graph can match a query more than once, you might prefer to export a graph as often as it matches the query. In this case please check the box Include all matches within a corpus graph.
Parameter: image includes
All corpus graphs are exported in a canonical form, i.e. as fully expanded graphs including match highlighting and match focussing. You can turn on/off the match highlighting, include/exclude the exact description of the match in the SVG navigation bar, and specify the background color. We recommend you to use transparent; in this case the SVG viewer is responsible for the selection of the background color.
To start the export process just press the Submit button. Please note that the export process cannot be stopped.
A popular SVG viewer is the SVG browser plugin which has been
developed by Adobe (cf. 
http://www.adobe.com/svg/viewer/install/).
This plugin is currently available for the Microsoft Windows
and Apple Macintosh platforms. Using this plugin, you can view an SVG
image in the Netscape and Internet Explorer browsers.
If you are interested in integrating SVG images in Microsoft PowerPoint
presentations, you should visit the following web page:
http://www.indezine.com/products/powerpoint/.
This page comprises a detailed description of the integration process. It also
contains interesting general hints to improve your PowerPoint presentations.
The default configuration of the TIGERGraphViewer has been defined in such a way that the visualization should work fine on all supported platforms. If you like to adapt the configuration according to your individual preferences, you can modify the display colors and the most important display parameters. Your modifications are saved when leaving the tool and restored at the beginning of your next TIGERSearch session.
Color options
To change the color settings of the GraphViewer, please select the Color options item in the Options menu. The display color windows appers:
Figure: Changing the color settings of the GraphViewer
In this window all colors used by the TIGERGraphViewer are listed and illustrated by the color of the respective choose button. To change a color, press the corresponding Choose button. Another window pops up that lets you select the new color. Select the preferred color and leave this window by pressing the OK button.
If you would like to restore your configuration (that has been valid before opening the color options window), just click the Reset button. To restore the default values that have been pre-installed for using the TIGERGraphViewer activate the Default button. To leave the window without changing the configuration press the Cancel button. To submit your changes press the OK button.
Display options
Some important display parameters used by the TIGERGraphViewer can also be changed. To open the display options window, please select the Display options item in the Options menu. The display options window appers.
Figure: Changing display parameters of the GraphViewer
The following general parameters can be modified:
Maximum width of terminal nodes
The maximum width of the terminal node visualization is limited. Thus, some feature values (especially word forms) may be truncated. If this occurs too often, just specify a higher width.
Display secondary edges
In order to turn on/off the display of secondary edges check/uncheck this box.
Display virtual root node
Some corpus formats such as the Negra format do not integrate special types of tokens (e.g. punctuations marks) into the graph annotation. Unfortunately, the TIGERSearch query processing algorithm only works on connected graphs. Hence, during the indexing process a virtual root node is inserted in any graph that comprises terminal nodes (e.g. punctuations marks) which are not integrated into the corresponding syntax graph. In order to turn on/off displaying of virtual root nodes check/uncheck this box.
Hide...
Sometimes annotating a token feature does not make sense for features such as morphological feature or case. In this case, a qualified symbol such as -- is used instead. We recommend you to use -- which is also used in our implemented import filters.
Since these symbols do not represent annotation information, it makes sense to hide them in the visualization. The two boxes must be checked if you want to hide a special feature value or edge label. Please specify the symbol which should be suppressed in the respective text fields.
The following corpus-depending parameters can be modified:
Displayed non-terminal feature
For non-terminal nodes, only one feature can be displayed in the GraphViewer. If there are two or more features defined for non-terminal nodes, the displayed feature can be changed in this dialog. By default, the non-terminal feature defined first in the TIGER-XML encoding is selected.
Displayed terminal features
By default, all features of the terminal nodes are displayed. If you like to reduce the number of displayed features, just deselect the features you are not ineterested in.
Please note: As these parameters are corpus-depending, they will be restored when the
corpus is used again (even within the next TIGERSearch session).
If you like to restore your configuration (that has been valid before opening the display options window), just click the Reset button. To restore the original system defaults that have been pre-installed for using the TIGERGraphViewer activate the Default button. To leave the window without changing the configuration press the Cancel button. To submit your changes press the OK button.