The class function assigns the first parameter to a class interval. The result is a dual value with a<=x<b as the textual value, where a and b are the upper and lower limits of the bin, and the lower bound as numeric value.
Syntax:
class(expression, interval [ , label [ , offset ]])
Arguments:
| Argument | Description |
|---|---|
| interval | A number that specifies the bin width. |
| label | An arbitrary string that can replace the 'x' in the result text. |
| offset | A number that can be used as offset from the default starting point of the classification. The default starting point is normally 0. |
Examples and results:
| Example | Result |
|---|---|
| class( 23,10 ) | returns '20<=x<30' |
| class( 23,5,'value' ) | returns '20<= value <25' |
| class( 23,10,'x',5 ) | returns '15<=x<25' |
In this example, we load a table containing name and age of people. We want to add a field that classifies each person according to an age group with a ten year interval. The source table looks like this:
| Name | Age |
|---|---|
| John | 25 |
| Karen | 42 |
| Yoshi | 53 |
To add the age group classification field, you can add a preceding load statement using the class function. In this example, we load the source table using inline data.
The resulting data that is loaded looks like this:
| Name | Age | Agegroup |
|---|---|---|
| John | 25 | 20 <= age < 30 |
| Karen | 42 | 40 <= age < 50 |
| Yoshi | 53 | 50 <= age < 60 |
