IBM Cognos, User Manual, Page: 114 / 411

Note: The Cognos Transformer expression editor is not the same expression editor
used in Framework Manager or the IBM Cognos studios.
When you build an expression, you select elements, one by one, from the
Available components list in the left pane of the expression editor and build your
expression in the right pane. The available elements vary according to the type of
calculation and the position in the expression. Explanations for each element are
provided in a
Tips window in the expression editor and, as you enter each
element, the syntax is evaluated against standard mathematical rules.
Tip:
If the Tips box is not visible, click the
Tips
button .
You can also copy or type your calculation directly into the
Expression definition
pane.
The supported functions for calculated measures are:
v
absolute
Returns the absolute value.
v average
Returns the average value.
v min
Returns the minimum value of selected data items.
v max
Returns the maximum value of selected data items.
v
percent
Returns the percent of the total value for the selected data items.
The supported arithmetic operators are + (addition), - (subtraction),
* (multiplication), / (division), and ^ (exponentiation).
The Cognos Transformer expression editor also supports if-then-else constructs and
brackets. The boolean portion of the if-then-else supports AND, OR, and isnull (a
function that tests if a measure value is empty).
For more information about the expression editor, see Appendix F, “IBM Cognos
Transformer Expression Editor,” on page 355.
Controlling How Measures Roll Up
The rollup function specifies how measure values are summarized, or rolled up,
from child categories to their parent categories. Summarization occurs when your
OLAP reporting component displays measure values in categories above the lowest
level of detail.
When the type of rollup used is specified in the Description box on the Measure
property sheet, other users can reference this information. The three kinds of rollup
are as follows:
v
Regular rollup combines records with identical values in non-measure columns.
It is applied to the time dimension by default unless the Time state rollup
option is specified for the measure.
v
Time state rollup combines records with identical values in the time dimension
according to the Time state rollup function selected.
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IBM Cognos Transformer Version 10.1.1: User Guide