How to import signal in SPTool (in Signal Analysis Application)?

Hello, I have a basic question on using SPTool signal analysis. I want to import an unevenly sampled time series signal. I have one vector y represent the measured data, and one vector x represents sampling time. How can I import x, avoiding assign one signal sampling frequency.

Thanks!

Answer 1

[Dimitris Iliou]

If I understand your question correctly, you are trying to use SPTool and import a single signal x, that has different sample times that are included in vector y.

SPTool will only allow you to have a scalar value in the Sampling Frequency field.

You can import the signal from the SPTool UI or create a signal component programmatically first. In both cases you will get the same outcome: Sampling Frequency needs to be scalar.

To create a sptool component programmatically, you can use the following command:

SignalTest = sptool('create','Signal',x,y,'test')

When you run this command you will get the following error:

Error using sptool (line 683)
Found the following error: The sampling frequency must be a positive real scalar.

In case you do create a component and then you try to change the Sampling Frequency to a vector, you will not get the desired result.

For example if you run:

SignalTest= sptool('create','Signal',x,1,'test');
SignalTest.Fs = y;

the resulting Sampling Frequency when you try to import the 'SignalTest' through SPTool, will be all the values of the vector concatenated into a scalar value.

In summary, the Sampling Frequency needs to be a scalar when using the SPTool.