def _zpklp2lp(z, p, k, wo=1):
 degree = _relative_degree(z, p)
 z_lp = [(wo * z1) for z1 in z]
 p_lp = [(wo * p1) for p1 in p]
 k_lp = (k * (wo ** degree))
 return (z_lp, p_lp, k_lp)

def _zpklp2lp ( z , p , k , wo = 1 ) : degree = _relative_degree ( z , p ) z_lp = [ ( wo * z1 ) for z1 in z ] p_lp = [ ( wo * p1 ) for p1 in p ] k_lp = ( k * ( wo ** degree ) ) return ( z_lp , p_lp , k_lp )
transform a lowpass filter prototype to a different frequency .