high_pass_filter

#High Pass Filter

##Description The HighPassFilter class implements a first-order infinite-impulse-response (IIR) high pass filter. The HighPassFilter is part of the Preprocessing Modules.

An example of a signal (sine wave at 0.1Hz, 0.5Hz, 1Hz, 2Hz, 4Hz and 8Hz) filtered using a high pass filter. The cutoff frequency of the filter is set to 2Hz. The red signal is the raw signal and the green signal is the filtered signal. The signal and filtered data was generated using the example code below.

##Advantages The HighPassFilter is good for removing a small amount of low frequency noise from an N dimensional signal. You can either remove this noise from the N dimensional signal by setting the filterFactor of the filter to a low value (i.e. a filterFactor value of 0.1 will result in a large amount of low frequency signal attenuation), alternatively, if you know the exact frequency of the noise you want to remove from the signal then you can explicitly set the cutoff frequency of the filter (using the setCutoffFrequency(...) function).

##Disadvantages Given that this filter is only a first-order filter, it may not give you a step enough cutoff frequency for the application you need.

##Example High Pass Filter Example