Append (RapidMiner Studio Core)

Synopsis

This operator builds a merged ExampleSet from two or more compatible ExampleSets by adding all examples into a combined set.

Description

This operator builds a merged ExampleSet from two or more compatible ExampleSets by adding all examples into a combined set. All input ExampleSets must have the same attribute signature. This means that all ExampleSets must have the same number of attributes. Names and roles of attributes should be the same in all input ExampleSets. Please note that the merged ExampleSet is built in memory and this operator might therefore not be applicable for merging huge data set tables from database. In that case other preprocessing tools should be used that aggregate, join, and merge tables into one table which is then used by RapidMiner.

Input

  • example set (Data Table)

    The Append operator can have multiple inputs. When one input port is connected, another input port becomes available which is ready to accept another input (if any).This input port expects an ExampleSet. It is output of the Retrieve operator in the attached Example Process. Output of other operators can also be used as input. It is essential that meta data should be attached with the data for the input because attributes are specified in their meta data. The Retrieve operator provides meta data along-with data.

Output

  • merged set (Data Table)

    The merged ExampleSet is delivered through this port.

Parameters

  • data_managementThis is an expert parameter. A long list is provided; users can select any option from this list. Range: selection

Tutorial Processes

Merging Golf and Golf-Testset data sets

In this process the 'Golf' data set and 'Golf-Testset' data set are loaded using the Retrieve operators. Breakpoints are inserted after the Retrieve operators so that you can have a look at the input ExampleSets. When you run the process, first you see the 'Golf' data set. As you can see, it has 14 examples. When you continue the process, you will see the 'Golf-Testset' data set. It also has 14 examples. The Append operator is applied to merge these two ExampleSets into a single ExampleSet. The merged ExampleSet has all examples from all input ExampleSets, thus it has 28 examples. You can see that both input ExampleSets had the same number of attributes, same names and roles of attributes. This is why the Append operator could produce a merged ExampleSet.