The purpose of this PAK Tip is to introduce the “Measurement Series Statistic” feature available since the release of PAK 6.0 in the “Graphic Definition”.
This feature makes it possible to perform statistical operations between different measurements, as it can also be done in the “Arithmetic” module.
This functionality can be used directly in the "Data Definition", from the "Additional" tab:
You must first define on which (single) channel you want to perform a statistical operation, choose the type of operation, and define which measurements to use.
In the example, we will use a run up, for a sensor position, and for 3 different measurements.
We first select a first measure (master):
We choose the measurement channel and the “data type” (Measurement and Graphic), here APS and Sum level:
In the Additional tab, we activate the functionality, we choose the type of evaluation to perform and on which Data Type (Measurement or Graphic), then we define the list of measurements to be used:
(Line 1 corresponds to the measure selected in the Graphic Definition to activate the line: that means it is the master)
For example, we choose “Average [Q]” to be calculated on the “Graphic Data Type”, in our example the “Sum level”:
As for a “classic” data display, the other tabs are entered (“Display / Filter”, “Track parameter” etc…).
In the end, we perform the “Graphic Output” to display the average of these 3 measurements:
The list of measurements to be used can be configured in different ways:
- By pointing directly to the names of measurement, or
- to an alias table, or
- to the "Last Tests"
You can also display the average of the 3 measurements, as well as a "Min Hold" and "Max Hold", detected on the same list of 3 measurements:
Bonus: A right-click on "copy all curves data" allows you to quickly retrieve the data to paste them into Excel for example.
The operation can be performed on 3D type data:
Note on tracking points:
It may happen that there are differences in the tracking values available between the different measurements considered for statistical operations. In this case, the statistical operation is performed on the available common values.
In this example, the “run1” and “run2” measurements do not start at the same rpm. The average is calculated from the first common point and available for the 2 measurements.