This example describes how to compare the average peak areas for two different sets of samples (for example, calibration samples and checkout samples, or samples with a name containing SampleA and samples with a name containing SampleB).
Add the Compound Results table two times to the template.
Filter the tables according to the samples for which you want to obtain the average peak areas.
|
Expression | Operation |
Value | Description |
|---|---|---|---|
|
=Sample_Type |
= | =1 | The first table contains only calibration samples. |
|
=Sample_Type |
= | =2 | The second table contains only checkout samples. |
In each table: Open the Column Properties dialog of the Area column, and save the value as a variable. Use the following settings:
Calculation Variables: Aggregator
Calculation Variable Name: For example, AreaAggregator1 in the first table, and AreaAggregator2 in the second table.
Category: [None]
Condition: [None]
Underneath the two tables, create a text field with the following expression: =Avg(AreaAggregator1) - Avg(AreaAggregator2)
Instead of the Avg function, you can also apply the Sum, Stdev, Prsd, Min, Max, or Count function to the Aggregator variables.
|
Clear function If you create and use the Aggregator inside a composite group, use the Clear function at the end of the group. Add two hidden text fields with the following expressions: =Clear(AreaAggregator1) =Clear(AreaAggregator2) This clears all contents of the Aggregator, which ensures that the values are not mixed in subsequent group repetitions. |