Getting Your Data In

In GUESS we are actively working to disentangle the frontend visualization from the backend data. However, for now we are still using the HSQLDB database to persistently store and access to this data. The database data can be persistent or in memory (For most smaller graphs this is ok, and you’ll want this for applets).

There are three ways to add data into the database. The first is to apply node and edge creation commands inside the GUESS interface. These nodes will automatically get pushed into the database. The second is a limited, but fairly functional graphml and Pajek loader (see notes in section 4.2). The final, and perhaps best way, to get your data in is to create a guess data file.

When you ran GUESS in the tutorial you may have noticed the set of questions in the beginning that walked you through loading the file/databases. The first menu lets you load up an existing (persistent) database or pick a file to load (see Figure 4a). This file can either be in GUESS format or GraphML (GraphML files must have the file type .xml or .graphml). If you select the “Load GDF/GraphML” you will select the file that contains your data. You will then be asked if you want this new file to be persistent or in memory (see Figure 4b). Selecting “in memory” will load the data into a memory resident database which will vanish once you quit GUESS. If you select “persistent” you will be instructed to pick a directory for your database files and then a name for the database (there end up being a few files that make the database persistent so you may want to create a “database” directory if you don’t like your directories to be littered with files). Note that in most newer versions of GUESS you can still save the state of the graph in a new GDF file so you can pretty safely ignore the persistent database stuff (but it is useful for really large graphs).

Even if you load up an empty graph you still have the option in the File menu to open up GDF, GraphML, and Pajek files. These will load on top of whatever graph you already have so you may want to delete all the nodes and edges before doing that. Also, the way graphs are loaded is optimized when GUESS starts so there is a performance cost to loading things from the menu once the visualization has started.