How to use frest.Sinestream to create a sine wave sound

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I use the code below to create a 6 secs long sine wave which contain 0~2 sec was 200 Hz, 2~4 sec was 100 Hz, 4~6 sec was 300 Hz.
result=frest.Sinestream('Amplitude',0.5,...
'Frequency',[200 100 300],...
'SamplesPerPeriod',ceil([44100/200 44100/100 44100/300]),...
'FreqUnits','Hz',...
'RampPeriods',[0.02/(1/200),0.02/(1/100),0.02/(1/300)],...
'NumPeriods',[200*2-4 100*2-2 300*2-6]);
The sine wave's sampling rate must be 44100 Hz, so each period's sample was according to it's frequency.(ex:0~2 sec was 200 Hz, so per period was 44100/200 samples.), and Ramp was 20ms long, so 200 Hz was 4 ramp period (0.02/(1/200)). and NumPeriods was 2 secs long each frequency. ex: 200 Hz*2-4(ramp period).
After that, the result was a Undefined function or method 'lt' for input arguments of type 'frest.Sinestream'. So it couldn't use wavwrite function to write into a wav file.
I found
x=generateTimeseries(result);
and x was a double timeseries, which x.Data can wavwrite into a wav file. Then I got a sine wave sound which has dynamic frequency. But, it was 6.0045 sec long, I found that the 0~2sec was incorrect. I though is because it's 'SamplesPerPeriod' was 44100/200=220.5 was not int. and I ceil it. How can I fix this problem?
Thanks

Accepted Answer

Arkadiy Turevskiy
Arkadiy Turevskiy on 19 Feb 2013
frest is part of Simulink Control Design. You need to have a license of this product to use frest. I ran your code and was able to get the signal you are trying to generate.
You can check the products on your license by typing
>>ver
HTH.
Arkadiy

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