ExpRegA (PQL)

* Click on the function's arguments above for more details on the input values.

Comments

The ExpRegX functions calculate the exponential regression for the supplied values / measures, and then return one of the values associated with that regression. The exponential regression functions are:

• ExpRegA (PQL) - Returns the value of a, the constant or initial value.
• ExpRegB (PQL) - Returns the value of b, the growth or decay factor.
• ExpRegPoint (PQL) - Returns the y-value for the regression line at a particular value of x.
• ExpRegR2 (PQL) - Returns the coefficient of determination, R².

Arguments

ExpRegA returns the value of a, the constant or initial value, and requires the following arguments:

• The List parameter is a list or set of elements from an existing hierarchy in the model.
• The hierarchy name needs to be a Unique Name with the format [dimension].^[hierarchy] or [table].[column].
• The Numeric parameters following the set are each evaluated against the specified set to obtain the values for the y- and x-axes, respectively.
• The values can be returned from a hierarchy as a numeric expression.
• If the optional numeric value is not supplied, the current context of the cells is used for the x-axis.

Remarks

• For details on how to employ and use this function see the semantic calculation overview.

Examples

When drawing an exponential regression across the last 10 date-key members, where Sales is regressed against Profit, the value of a (the constant or initial value) is returned using the following function:

ExpRegA( Tail([Date].[dateKey].allmembers, 10), [Measures].[Fact Sales], [Measures].[Profit] )

Tip: Alternatively, use Last in place of Tail. Last and Tail are aliases for the function that retrieves the last X elements in a given hierarchy. For more information, see Tail (PQL).