Overview of iTool Data Management

The iTools system is designed to turn raw data — numbers stored in computer memory — into visualizations that convey information to the viewer. Using data to create a visual display requires some way to route each piece of data to the appropriate part of the algorithm that displays it. In the terminology used by the iTool system, each data item must be associated with a parameter of a visualization.

The iTools system manages the relationship between data and the visualizations that display data via two mechanisms: iTool data types and parameter data types. The iTool data type is a property of an IDLitData object (or of an object that inherits from the IDLitData object); it can be any valid scalar string. iTool data types are described in detail in iTool Data Types. Parameter data types are assigned when a visualization object registers its parameters with the iTool system; they also can be any valid scalar string. Parameter data types are described in Parameters.

Note
iTool operations, which do not support the concept of parameters or parameter names, determine whether they can act on a given data object solely on the basis of the iTool data type.

The iTool data type and parameter data types are used to match up data objects with visualizations that need data to display. See Data Type Matching for a description of how matches are made.

This chapter describes data-management tasks undertaken by the iTool developer. Interactive users manipulate data using a graphical interface known as the iTool Data Manager; this interface allows the user to select and import data items into the iTool system and to manually associate data items with parameters. See Importing and Exporting Data (iTool User's Guide) for a complete description of the Data Manager and its use.