Hello,(adsbygoogle = window.adsbygoogle || []).push({});

In order to test-drive a data analysis program, I am looking for a function that generates sine waves with slowly oscillating frequency, i.e. the distance between the maxima should be slowly changing.

I thought that I could simply achieve this by using a function of the form

[tex]

f(t) = \sin\Bigl( 2 \pi t \bigl[ 5 + \cos( 2 \pi t / 10 ) \bigr] \Bigl)

[/tex]

and expected to get something that oscillates with a frequency that slowly changes between 4 and 6 over when t goes from 0 to 10.

However, the function behaves in a very different way. It reaches a maximum of f(t)~0.5 at t~3 and has to minima very close to each other at t~4.2.

Can someone help me to understand (a) why the above function doesn't behave the way I expect it to and (b) what function I could use to generate the desired data?

Best,

Nikolaus

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# Wave with oscillating frequency

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