Electronic documents may contain a graph to present some specific data in a visual way. To produce such an electronic document with a computer, the user may specify a type of graph and enter source data to the computer. In response, the computer generates a graph according to the user input by running a software program having graph generation functions.
The software used for graph generation may be, for example, spreadsheet applications. A spreadsheet program running on a computer enables the user to enter data in table form and produce a user-specified type of graph from the data table. Graphs may similarly be produced with other application software for designing and creating documents such as business forms. This software generates a graph from given source data and inserts the resulting graph into a document.
There is also proposed a document processing device that helps the user to create a diagram suitable for the purpose of his or her document, without any special knowledge about the format of such diagrams. The proposed device accepts user commands that specify the purpose of a diagram to be created, together with a set of rules describing how the diagram is to represent its content. In response, the document processing device determines appropriate color arrangement, object layout and decoration for the diagram. See, for example, Japanese Laid-open Patent Publication No. 2000-268112.
An electronic document such as a business form may include a bar graph, line graph, or other kind of charts, depending on the purpose of the document, i.e., what kind of information the graph is intended to deliver. For example, bar graphs may be selected when the user intends to provide comparison among a plurality of data values in terms of their magnitude. Line graphs may be intuitive in many cases when it is intended to depict the variations of two or more data items with time.
It has to be noted that, in the conventional techniques discussed above, the selection of which type of graph to generate is up to the user. This means, however, that the user does not always make a right choice of graphs. If a wrong type was specified, the resulting graph would be difficult to understand, the user would thus have to spend extra time to discard the useless graph and to create another graph by specifying a different graph type.