Provide consistent valid logic to operators by providing a QDataSet with 1.0 where the data is valid, and 0.0 where the data is invalid. VALID_MIN, VALID_MAX and FILL_VALUE properties are used. Note, when FILL_VALUE is not specified, -1e31 is used. This is to support legacy logic. The property FILL_VALUE is no longer set to the fill value used. https://sourceforge.net/p/autoplot/bugs/1458/ SUGGEST_FILL will be set in the properties.