Indicates the shape of the filter FILT_ORDER
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filt_..."
parameters are hard-edged. That is, they change from zero to one without
any intermediate values. If filt_order is larger than zero, the edge filters are soft-edged Butterworth filters with
order given by the value of this parameter. An order of 1 is the softest, and will thus produce least ringing, at the
expense of poorer frequency response. Higher orders produce sharper filters that have better frequency
response but at the expense of greater ringing. [0]