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Graph measurment converts integer to float?

EmilFernlund 1 month ago in IQANdesign updated by Gustav Widén (System support) 1 month ago 3

Measured data over ethernet apperas to be manipulated at the  end of a measurment. 

During the actual measurment over ethernet the integers apper to be integers as they should.

When measurment is stopped, the values of integer math channels and Generic parameter in channels change from integers to decimal values. 

 

The values in the attached image that are converted to decimal values are either Generic parameter in or integer math channels. Event counters and internal digital channels stay as integers.

What is your cycle time? 

Have you seen if there are missing samples in the graph? 

(marked with a slightly different background color in the graph, you enable/disable this with "mark missing samples" under options)

I am not sure, but I am guessing maybe you are seeing the effect of interpolation between missing samples. 

 

Cycle time is 10ms, with ~12% cycle utilization.
Yes, there is alot of missing samples during measurment over ethernet. 
I am also guessing that it's an effect of interpolation. But why is only some parameters interpolated and not all? 

Edited the title that previously said "ethernet measurment converts integer to float", as it does not matter what communication interface you use. 

When you graph, both integers and reals are stored as value type real. 

But when viewing the values, IQANrun is showing even numbers without decimal points. 

All values that has changed between missing samples are interpolated.