Set Macro (Real)
(Operator Toolbox)
Synopsis
This operator can be used to define a macro which can be used by %{macro_name} in parameter values of succeeding operators of the current process. The difference to the usual Set Macro operator is a numeric parameter for the macro value, which can be used with optimize operators. The macro value will NOT be derived from any ExampleSet. A macro can be considered as a value that can be used by all operators of the current process that come after the macro has been defined. This operator can also be used to re-define an existing macro.Description
This operator can be used to define a macro which can be used in parameter values of succeeding operators of the current process. Once the macro has been defined, the value of that macro can be used as parameter values in coming operators by writing the macro name in %{macro_name} format in the parameter value where 'macro_name' is the name of the macro specified when the macro was defined. In the Set Macro operator, the macro name is specified by the macro parameter and the macro value is specified by the value parameter. The macro will be replaced in the value strings of parameters by the macro's value. This operator can also be used to re-define an existing macro.
This operator sets the value of a macro irrespective of any ExampleSet. That is why this operator can also exist on its own i.e. without being connected to any other operator. If you want to create a single macro from properties of a given input ExampleSet, the Extract Macro operator is the right operator.
Macros
A macro can be considered as a value that can be used by all operators of the current process that come after the macro has been defined. Whenever using macros, make sure that the operators are in the correct sequence. It is compulsory that the macro should be defined before it can be used in parameter values. The macro is one of the advanced topics of RapidMiner, please study the attached Example Process to develop a better understanding of macros. The Example Processes of the Extract Macro operator are also useful for understanding the concepts related to the macros.
There are also some predefined macros:
- %{process_name}: will be replaced by the name of the process (without path and extension)
- %{process_file}: will be replaced by the file name of the process (with extension)
- %{process_path}: will be replaced by the complete absolute path of the process file
- Several other short macros also exist, e.g. %{a} for the number of times the current operator was applied.
Please note that other operators like many of the loop operators (e.g. Loop Values , Loop Attributes) also add specific macros.
During the runtime the defined macros can be observed in the macro viewer.
Differentiation
Set Macro
The Set Macro operator included in RapidMiner Studio has a nominal parameter. The Set Macro (Real) operator exposes a real parameter. This can be handy if you want to optimize on a macro e.g. in Optimize Parameters.
Set Macros
The Set Macros operator is like the Set Macro operator with only one difference. The Set Macros operator can be used for setting values of multiple macros whereas the Set Macro operator can be used for setting value of just a single macro.
Input
through (Data Table)It is not compulsory to connect any object with this port. Any object connected at this port is delivered without any modifications to the output port. This operator can have multiple inputs. When one input is connected, another through input port becomes available which is ready to accept another input (if any). The order of inputs remains the same. The object supplied at the first through input port of the Set Macro operator is available at the first through output port.
Output
- through (Data Table)
Objects that were given as input are passed without changing to the output through this port. It is not compulsory to attach this port to any other port, the macro value is set even if this port is left without connections. The Set Macro operator can have multiple outputs. When one output is connected, another through output port becomes available which is ready to deliver another output (if any). The order of outputs remains the same. The object delivered at the first through input port of the Set Macro operator is delivered at the first through output port
Parameters
- macroThis parameter is used to specify the name of the macro. The macro can be accessed in succeeding operators of the current process by writing the macro's name in %{macro_name} format, where 'macro_name' is the name of the macro specified in this parameter. Range:
- valueThis parameter is used to specify the value of the macro. When the macro is accessed in succeeding operators of the current process by writing the macro's name in %{macro_name} format, it is replaced by the value of the macro specified by this parameter. Range:
Tutorial Processes
Optimize Survival Probability for Titanic Using Set Macro (Real)
In this process we model the probability to survive the titanic disaster using a Deep Learning operator. In the second step optimize the best Fare for a single passenger. This is done using Optimize Parameters (Evolutionary) and Set Macro (Real).
