(AI Studio Core)
Synopsis
This operator changes the type of the selected real attributes to integer type. It also maps all values of these attributes to integer values.Description
The Real to Integer operator converts selected real attributes to integer valued attributes. Each real value is either cut or rounded off and then used as an integer value of the new attribute. This option is controlled by the round values parameter. If it is set to false, the decimal portion of the real value is simply truncated otherwise it is rounded off. If the real value is missing, the new integer value will be missing.
Input
- example set input (Data table)
This input port expects an ExampleSet. It is the output of the Retrieve operator in the attached Example Process. The output of other operators can also be used as input. The ExampleSet should have at least one real attribute because if there is no such attribute, the use of this operator does not make sense.
Output
- example set output (Data table)
The ExampleSet with selected real attributes converted to integer type is output of this port.
- original (Data table)
The ExampleSet that was given as input is passed without changing to the output through this port. This is usually used to reuse the same ExampleSet in further operators or to view the ExampleSet in the Results Workspace.
Parameters
- attribute filter typeThis parameter allows you to select the attribute selection filter; the method you want to use for selecting the required attributes. It has the following options:
- all: This option simply selects all the attributes of the ExampleSet. This is the default option.
- single: This option allows selection of a single attribute. When this option is selected another parameter (attribute) becomes visible in the Parameters panel. (Since RapidMiner 6.0.4 the Operator will fail if a selected Attribute is not in the ExampleSet)
- subset: This option allows selection of multiple attributes through a list. All attributes of the ExampleSet are present in the list; required attributes can be easily selected. This option will not work if the meta data is not known. When this option is selected another parameter becomes visible in the Parameters panel. (Since RapidMiner 6.0.4 the Operator will fail if a selected Attribute is not in the ExampleSet)
- regular expression: This option allows you to specify a regular_expression for attribute selection. When this option is selected some other parameters (regular expression, use except expression) become visible in the Parameters panel.
- value type: This option allows selection of all the attributes of a particular type. It should be noted that types are hierarchical. For example real and integer types both belong to the numeric type. Users should have a basic understanding of type hierarchy when selecting attributes through this option. When it is selected some other parameters (value type, use value type exception) become visible in the Parameters panel.
- block type: This option is similar in working to the value type option. This option allows selection of all the attributes of a particular block type. When this option is selected some other parameters (block type, use block type exception) become visible in the Parameters panel.
- no missing values: This option simply selects all the attributes of the ExampleSet which don't contain a missing value in any example. Attributes that have even a single missing value are removed.
- numeric value filter: When this option is selected another parameter (numeric condition) becomes visible in the Parameters panel. All numeric attributes whose examples all satisfy the mentioned numeric condition are selected. Please note that all nominal attributes are also selected irrespective of the given numerical condition.
- attributeThe desired attribute can be selected from this option. The attribute name can be selected from the dropdown box of attribute parameter if the meta data is known.
- attributesThe required attributes can be selected from this option. This opens a new window with two lists. All attributes are present in the left list and can be shifted to the right list which is the list of selected attributes on which the conversion from nominal to numeric will take place; all other attributes will remain unchanged.
- regular expressionThe attributes whose name matches this expression will be selected. Regular expression is a very powerful tool but needs a detailed explanation to beginners. It is always good to specify the regular expression through the edit and preview regular expression menu. This menu gives a good idea of regular expressions. This menu also allows you to try different expressions and preview the results simultaneously. This will enhance your concept of regular expressions.
- use except expressionIf enabled, an exception to the selected type can be specified. When this option is selected another parameter (except value type) becomes visible in the Parameters panel.
- except regular expressionThis option allows you to specify a regular expression. Attributes matching this expression will be filtered out even if they match the first expression (expression that was specified in the regular expression parameter).
- value typeThe type of attributes to be selected can be chosen from a dropdown list. One of the following types can be chosen: nominal, text, binominal, polynominal, file_path.
- use value type exception If enabled, an exception to the selected type can be specified. When this option is selected another parameter (except value type) becomes visible in the Parameters panel.
- except value typeThe attributes matching this type will be removed from the final output even if they matched the previously mentioned type i.e. value type parameter's value. One of the following types can be selected here: nominal, text, binominal, polynominal, file_path.
- block typeThe block type of attributes to be selected can be chosen from a dropdown list. The only possible value here is 'single_value'
- use block type exceptionIf enabled, an exception to the selected block type can be specified. When this option is selected another parameter (except block type) becomes visible in the Parameters panel.
- except block typeThe attributes matching this block type will be removed from the final output even if they matched the previously mentioned block type.
- numeric conditionThe numeric condition for testing examples of numeric attributes is specified here. For example the numeric condition '> 6' will keep all nominal attributes and all numeric attributes having a value of greater than 6 in every example. A combination of conditions is possible: '> 6 && < 11' or '<= 5 || < 0'. But && and || cannot be used together in one numeric condition. Conditions like '(> 0 && < 2) || (>10 && < 12)' are not allowed because they use both && and ||. Use a blank space after '>', '=' and '<' e.g. '<5' will not work, so use '< 5' instead.
- include special attributesThe special attributes are attributes with special roles which identify the examples. In contrast, regular attributes simply describe the examples. Special attributes are: id, label, prediction, cluster, weight and batch.
- invert selectionIf this parameter is set to true, it acts as a NOT gate, it reverses the selection. In that case all the selected attributes are unselected and previously unselected attributes are selected. For example if attribute 'att1' is selected and attribute 'att2' is unselected prior to checking of this parameter. After checking of this parameter 'att1' will be unselected and 'att2' will be selected.
- round valuesThis parameter indicates if the values should be rounded off for conversion from real to integer. If not set to true, then the decimal portion of real values is simply truncated to convert the real values to integer values.
Tutorial Processes
Real to integer conversion of attributes of the Iris data set
The 'Iris' data set is loaded using the Retrieve operator. A breakpoint is inserted here so that you can have a look at the ExampleSet. You can see that the ExampleSet has four real attributes i.e. a1, a2, a3 and a4. The Real to Integer operator is applied on the 'Iris' data set to convert the type of these real attributes to integer. All parameters are used with default values. The resultant ExampleSet can be seen in the Results Workspace. You can see that now the type of these attributes is integer.