Specifications

CHAPTER 24 DataWindow Expression and InfoMaker Functions
Users Guide 757
Settings for Rows include the following:
• For the Graph presentation style, Rows is always All.
• For Graph controls, Rows can be All, Page, or Group.
• For OLE controls, Rows can be All, Current Row, Page, or Group. The
available choices depend on the layer the control occupies.
Estimating variance or calculating actual variance
Var assumes that the values in column are a sample of the values in rows in the
column in the database table. If you select all rows in the column in the
SELECT statement, use VarP to compute the variance of a population.
Not in validation rules or filter expressions
You cannot use this or other aggregate functions in validation rules or filter
expressions.
Using an aggregate function cancels the effect of setting Retrieve Rows As
Needed in the painter. To do the aggregation, a report always retrieves all rows.
Examples These examples all assume that the SELECT statement did not retrieve all of
the rows in the database table.
Var is intended to work with a subset of rows,
which is a sample of the full set of data.
This expression returns an estimate for the variance of the values in the column
named salary:
Var(salary)
This expression returns an estimate for the variance of the values in the column
named salary in group 1:
Var(salary for group 1)
This expression entered in the Value box on the Data property page in the
graph’s property sheet returns an estimate for the variance of the values in the
quantity column in the graph:
Var(quantity for graph)
This expression for a computed field in a crosstab returns an estimate for the
variance of the values in the quantity column in the crosstab:
Var(quantity for crosstab)