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displaying multiple ftt formats onto one graph

Using LabView 8
 
I am using several FTT analyzers (Hamming, Blackman, Flattop) from one signal source.  Each of the analyzers will then be displayed onto the same wavefrom graph with all the same Xo and dX.  I created a bundle for the waveform to accept Xo, dX and the Y coming from the Peak signal of the spectral analyzers.  The Y works if i only use one Peak signal, but i was hoping to be able to use multiple signals.  What i've noticed so far is that the source signal first must be converted from an array type to a dynamic data type.  This goes to the input of the FTT analyzers.  The Peak output then must be changed back to an array format so that it can be used for the Y on the bundle with Xo and dX.  When i merge the three Peak outputs to be changed to an array and then sent to the Y, there are no errors produced.  What happens though is that only one graph is produced and the Xo and dX scales are not correct.  The Y axis produces either straight lines or triangular shaped lines, nothing near peak outputs.  My question is, how do i merge the arrays properly so that the waveform graph can display the 3 seperate lines?
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Hi!

As long as your spectrums have the same number of points as well as the same dx and X0 this should be simple. Take a look at the VI below. It simulates 3 signals and display them on a waveform graph. I added a picture of the code in case you don't have labview 8. The code simply builds a 2D-array from 3 1D-arrays and bundles them into a cluster together wit dx and X0. The order should be: 1) dx 2) X0 3)Array counted from top.

Regards,

Einar

Message Edited by einarsto on 05-25-2006 03:39 PM

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ooops, a little typo sneaked into my reply. The order of elements in the cluster should be:

1) X0

2) dx

3) Array

 

Einar

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THank you sir, worked like a charmSmiley Very Happy
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