How to change the properties of waveform graph from time domain to frequency domain?

[Mal1279]

Actually, I want my output waveform graph give me the answer in x-component in frequency instead of time after the FFT. My output waveform graph gives the x-components in time instead of frequency. How to change the properties of the waveform graph?

[Greg_McKaskle2]

> Actually, I want my output waveform graph give me the answer in
> x-component in frequency instead of time after the FFT. My output
> waveform graph gives the x-components in time instead of frequency.
> How to change the properties of the waveform graph?

If you have already taken the FFT, then you can probably just change the
label below the X Scale to read whatever you like. If the X scale is
formatting the number as time, right click on the scale and choose
Formatting. Change the formatting to decimal, scientific, whatever you
like.

Greg McKaskle

[St Augustine]

i have a similiar problem.So what you are saying is that by just changing the scale to decimal after the FFT is taken means that the unit is in frequency?

[sardarsree]

Hi,

       I amtaking sensor input signals through NI FPGA cRIO-9004. i am analysing this using wave graph. the problem is i am not getting accurate singal.How to decrease the frequency? 

[TCPlomp]

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vasus wrote:

Hi,

       I amtaking sensor input signals through NI FPGA cRIO-9004. i am analysing this using wave graph. the problem is i am not getting accurate singal.How to decrease the frequency? 

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You are responding to a very old (8 years) thread, be aware that that might not be the best option.

However, you want to decrease the frequency? or increase?

What is the code you are running?

Ton

[sardarsree]

I am using labview 8.6. i added history of wavechart to wave graph. Then i taking one speed sensor's output through fppa analog input module. In graph i want to decrease frequency to analyse graph easily..

[Deepak Arora]

Hi Vasus,

I am not sure if I understand your questions correctly, though here are my suggestions,

- After performing FFT on a time domain waveform,  you get a signal in the fourier space with the x-axis being the frequency domain. So as far as I know, you do not need to any conversions. If you refering to the waveform axis label being time, you can just change that to Hz or whatever. It is just the label, no math.

- About decreasing the frequency, if you are using a waveform generator then you should have the control to do that. If you just want to limit the scale on waveform graph, there are two approaches,

                           1. Just right click on the graph and disable auto scaling. Click on any number on the axis and change that to the number that you want.

                           2. A better way is using the property node, you can automate the scale range.

Cheers,
Deepak