Returns the average value in a dataset field among records which satisfy a certain condition.
dataset_avg_ex( StepNo Integer, GroupLevel Integer, FieldName String, Condition String ): Numeric
StepNo specifies the export step, in which the function must be calculated. It is used in HTML export context only; in other cases this parameter is ignored.
GroupLevel is reserved for future use and currently must be 0.
FieldName is the name of the field to calculate.
Condition is a boolean expression. But it must be written as a String constant (i.e. enclosed in single quotes) or a string deterministic expression.
Examples of using
dataset_avg_ex( 1, 0, 'Salary', 'dataset_field_val(1, ''Age'') > 50' )