The numExt function returns a string containing only the numerical characters of the input string. If more than one number is present, numbers are delimited by a separator decided by the user (by default "-").
numExt(column, onlyint, separator)
If you are using continuous attributes, check the Flow Execution Parameters.
The nominal attribute used to evaluate the numeric extraction. If it is not nominal, it will be casted to nominal upon function’s computation. The column parameter is mandatory.
If it is True, or not specified, only integer values will be extracted, while if it is False, also continuous values will be extracted.
The separator used in case of multiple number extraction. It is '-' as default.
The following example uses the Bike sales dataset.
In this example, we want to create a new attribute, filled with the ages of the Age_Group attribute.
Add a new attribute, which we have called age, and type the following formula:
and the attribute will be filled with the numbers only.