06-25-2012 01:43 PM
Hi,
I want to convert dyanmic data to single scaler, however, the amplitude of the output is always smaller than the input signal.
Does any know why? thanks!!!!!!!!!!!!=)
plz see the attachment.
06-25-2012 02:04 PM
Hi,
Can you save the vi at older version?, i have 2009.
Best Regards,
06-25-2012 02:11 PM
Hi Luis,
I save it to version 8.6.=)
06-25-2012 02:27 PM
Not sure what you mean by 'smaller'. With the evil dynamic data type, the conversion takes the last element in the Y array. What are you expecting?
06-25-2012 02:29 PM
Hi nozombie,
I cannt run your vi, i dont have someones .vi, but i run a similar test and both signals look equals.
Can you post a print screen and explain a little more where is the difference?
Best Regards,
06-25-2012 02:42 PM
Hi Dennis,
If you run the vi i attached, you can see that the bottom right graph on the front panel has an amplitude of 0.75 instead of 1. However, my original input signal has an amplitude of 1.=)
Ivy
06-25-2012 02:48 PM
Hi Luis,
Thank you for ur reply 😃
As u can see from the picture, i use a simulate signal as the input(sine wave with an amplitude of 1). First i feed the signal into a downsampler function. The output is waveform data type. Then I convert it to dynamic data type and then to single scalers. However, after i convert it to single scaler, the amplitude of the signal changes to be 0.75 instead of 1. That's the problem 😃
Ivy
06-25-2012 02:59 PM
I can't run your code due to missing VIs, but could it be the data is being converted? I don't think it's being converted to RMS voltage, since your measurement is too high, but it could be related to something similar.
06-25-2012 03:15 PM
I can't run it either and since you did not save the front panel with typical data, there is nothing to actually look at. Again, I'll ask what do you expect to get from the conversion to a scalar when you have an array of values?
06-25-2012 03:17 PM
Hi nozombie,
What downsampler parameters are you using? Why a downsampler and not a decimate function? I think if you downsample much, you can lost someone peak values.
Best Regards,