The Selection Component or Parameter Selection panel, as shown in Figure 4-1, is located at the bottom of each Renderer window. Its purpose is to present the data that is accessible by this particular window. For example, if a Renderer window is opened for cross-sections of U235 in jef2.2 evaluation of a database, the Selection Component displays a list of reactions available for this nucleus, as well as any data resonances. Since Janis organizes data hierarchically using DataNode objects as parents for one or more DataLeaf objects, this data is presented in the form of a tree in the Selection Component. The Selection Component enables the user to select which data is to be displayed. This choice is presented in the form of selection boxes. There is one box per DataLeaf object. The Selection Component also provides access to various parameters. For example, some parameters are used to specify colors in plots and headings for tables.
Figure 4-1. Renderer window for cross-section of Uranium, U235 from jef22.
The Selection Component consists of a table that contains one line for each reaction or work number. These items are stored as DataNode and DataLeaf objects. The table has three columns: column one displays the data, such as reaction or works, in the form of a tree, column two provides display parameters, such as a plot color that may be changed, and column three displays the box for selection and deselection of data to be displayed.
The Selection Component has the followings purposes:
· management of the list of accessible data by the Renderer window containing them.
· management of the choice of data display.
· management of the current selection. This makes it possible for the Renderer to display the corresponding tabbed viewer component.
In Janis there are four possible ways of representing data. These notations appear in column three with the heading Display in Figure 4-77.
· [P] for graphical plots of cross-sections, energy and angular distributions, fission yields, or decay spectra.
· [T] for tabular data of resonance parameters, x,y representation of cross-sections or discrete decay spectra.
· [I] for information text, such as decay data constants or general information.
· [D] for decay path data.