Справочник Пользователя для ITT Rule IDL Version 7.0
Chapter 3: Data Management
61
iTool Developer’s Guide
Parameters
Parameters
Parameters represent data items used in a well-defined way by an algorithm that is
computing a result. In the scheme of the iTools, parameters are the raw material fed
to visualization objects — the IDL routines that create visual displays.
computing a result. In the scheme of the iTools, parameters are the raw material fed
to visualization objects — the IDL routines that create visual displays.
For example, a visualization object that creates a simple line plot might require two
parameters: vectors of dependent and independent data values. These two vectors
would be passed to the routines within the visualization object for processing, and the
result would be displayed in the iTool window.
parameters: vectors of dependent and independent data values. These two vectors
would be passed to the routines within the visualization object for processing, and the
result would be displayed in the iTool window.
When a visualization object is created, it registers one or more parameters with the
iTool system. Each parameter has a parameter name and can be of one or more iTool
data types. Parameter names are used to route the individual data items to the correct
routines within the visualization object. See
iTool system. Each parameter has a parameter name and can be of one or more iTool
data types. Parameter names are used to route the individual data items to the correct
routines within the visualization object. See
for
more on creating visualization objects.
Note
Do not confuse parameters, which define how data is used by a visualization object,
with parameter sets, which are containers for data objects. Parameter sets are
described in
with parameter sets, which are containers for data objects. Parameter sets are
described in
Parameter Names
Each parameter registered by a visualization is given a parameter name. The
parameter name is a scalar string, and its scope is the visualization by which it is
registered. Different visualizations can register parameters that have different
properties using the same parameter name.
parameter name is a scalar string, and its scope is the visualization by which it is
registered. Different visualizations can register parameters that have different
properties using the same parameter name.
Parameter Data Types
Each parameter registered by a visualization is associated with one or more iTool
data types by setting the TYPES property. The value of the TYPES property can be a
scalar string or a string array; a single parameter can be associated with multiple data
types. See
data types by setting the TYPES property. The value of the TYPES property can be a
scalar string or a string array; a single parameter can be associated with multiple data
types. See
on page 54 for more on iTool data types.
Registering Parameters
Parameters are registered when a visualization is created; that is, in the Init method of
an iTool visualization class. To register a parameter, call the RegisterParameter
an iTool visualization class. To register a parameter, call the RegisterParameter