Avg DataWindow expression function

Description

Calculates the average of the values of the column.

Syntax

<span>Avg</span> ( <span>column</span> { FOR <span>range</span> { DISTINCT { <span>expres1</span> {, <span>expres2</span> {, ... } } } } } )

1	<span>Avg</span> ( <span>column</span> { FOR <span>range</span> { DISTINCT { <span>expres1</span> {, <span>expres2</span> {, ... } } } } } )

Argument	Description
column	The column for which you want the average of the data values. Column can be the column name or the column number preceded by a pound sign (#). Column can also be an expression that includes a reference to the column. The datatype of column must be numeric.
FOR range (optional)	The data that will be included in the average. For most presentation styles, values for range are: ALL – (Default) The average of all values in column. GROUP n – The average of values in column in the specified group. Specify the keyword GROUP followed by the group number: for example, GROUP 1. PAGE – The average of the values in column on a page. For Crosstabs, specify CROSSTAB for range: CROSSTAB – (Crosstabs only) The average of all values in column in the crosstab. For Graph and OLE objects, specify one of the following: GRAPH – (Graphs only) The average of values in column in the range specified for the Rows option. OBJECT – (OLE objects only) The average of values in column in the range specified for the Rows option.
DISTINCT (optional)	Causes Avg to consider only the distinct values in column when calculating the average. For a value of column, the first row found with the value is used and other rows that have the same value are ignored.
expresn (optional)	One or more expressions that you want to evaluate to determine distinct rows. Expresn can be the name of a column, a function, or an expression.

Return Values

The numeric datatype of the column. Returns the average of
the values of the rows in range.

Usage

If you specify range, Avg returns
the average value of column in range.
If you specify DISTINCT, Avg returns the average
value of the distinct values in column, or
if you specify expresn, the average of column for
each distinct value of expresn.

For graphs and OLE objects, you do not select the range when
you call the function. The range has already been determined by
the Rows setting on the Data property page (the Range property),
and the aggregation function uses that range. Settings for Rows
include the following:

For the Graph or OLE
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.

In calculating the average, null values are ignored.

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 DataWindow object always retrieves
all rows.

Examples

This expression returns the average of the values
in the column named salary:

<span>Avg</span>(salary)

1	<span>Avg</span>(salary)

This expression returns the average of the values
in group 1 in the column named salary:

<span>Avg</span>(salary for group 1)

1	<span>Avg</span>(salary for group 1)

This expression returns the average of the values
in column 5 on the current page:

<span>Avg</span>(#5 for page)

1	<span>Avg</span>(#5 for page)

This computed field returns Above Average if the
average salary for the page is greater than the average salary:

If(<span>Avg</span>(salary for page) &gt; <span>Avg</span>(salary), "Above Average", " ")

1	If(<span>Avg</span>(salary for page) > <span>Avg</span>(salary), "Above Average", " ")

This expression for a graph value sets the data to
the average value of the sale_price column:

<span>Avg</span>(sale_price)

1	<span>Avg</span>(sale_price)

This expression for a graph value sets the data value
to the average value of the sale_price column for the entire
graph:

<span>Avg</span>(sale_price for graph)

1	<span>Avg</span>(sale_price for graph)

Assuming a DataWindow object displays the order number,
amount, and line items for each order, this computed field returns
the average of the order amount for the distinct order numbers:

<span>Avg</span>(order_amt for all DISTINCT order_nbr)

1	<span>Avg</span>(order_amt for all DISTINCT order_nbr)

Avg – PB Docs 126