using measurement studio 2009 for vb.net is there a way of getting the frequency of a scatter graph?

[johno45]

After i plot my graph i am able to get the max and min values using arrayname.max and arrayname.min is there a similar way of getting the frequency from the graph? any help help would appreciated!

john

[James_McN]

Hi John,

Getting the frequency of your data is going to be more complex than min or max as there will be multiple frequencies with multiple different levels.

To get frequency data you will need to get the power spectrum.  There are functions available for this in the Pro and Enterprise editions of Measurement Studio.  The simplest is the Measurements.AutoPowerSpectrum() function.  This takes your array of data and a dt (The time between samples) and returns an array of powers at different frequencies (Again an array and a df).

If you are looking for a specific peak frequency then you just need to find the frequency with the highest power from this array.  This could just be using the Max method or there is a peak detector in the Monitoring namespace.

Hope this helps, let me know if theres any more information you need.

Cheers,