butter function (signal)

Dear Sir or Madam,

At the University Medical Center Hamburg-Eppendorf, my research group would like to apply your package “signal” in R.

We have collected motion data with a balance board and would like to use the function “butter” to apply a high- and low-pass filter.

However, I was wondering how to convert the desired hertz values into radians in order to use the correct cutoff values.

Can you help us with this?

Many thanks and best regards

Maren Schlereth

w=2 * pi * f