biquada — A sweepable general purpose biquadratic digital filter with a-rate parameters.
iskip (optional, default=0) -- if non-zero, intialization will be skipped. Default value 0. (New in Csound version 3.50)
asig -- input signal
biquada is a general purpose biquadratic digital filter of the form:
  a0*y(n) + a1*y[n-1] + a2*y[n-2] = b0*x[n] + b1*x[n-1] + b2*x[n-2]
      
This filter has the following frequency response:
         B(Z)   b0 + b1*Z-1  + b2*Z-2
  H(Z) = ---- = ------------------
         A(Z)   a0 + a1*Z-1  + a2*Z-2
      
This type of filter is often encountered in digital signal processing literature. It allows six user-defined a-rate coefficients.