Values unit

A values units describes how values of a data item need to be interpreted. A values unit consists of:

  1. a value type (required) which need to correspond to the type of data values configured with this values unit. The value type of the values unit defines the data type, dimension and allowed range of values, see the value-type table.
  2. a metric (optional, advised for units describing quantities) defining how the values need to be interpreted semantically (in meters, seconds, etc.).

Values units describe data items with a similar range of values. This makes these units suitable for the configuration of a default-classification-scheme (cdf property).


Values units can be split up into:

  1. base units : units for which the metric is explicitly configured with the baseunit function,
  2. derived units : units configured with expressions, combining other units, parameters and literals. The metric results from the configured expression.
  3. value types: value types can also be used als values unit. For numerical data, this is not advised as the metric of values units is useful in interpreting your data and in preventing illogical calculations.