def _zpklp2hp(z, p, k, wo=1.0):
 z = atleast_1d(z)
 p = atleast_1d(p)
 wo = float(wo)
 degree = _relative_degree(z, p)
 z_hp = (wo / z)
 p_hp = (wo / p)
 z_hp = append(z_hp, zeros(degree))
 k_hp = (k * real((prod((- z)) / prod((- p)))))
 return (z_hp, p_hp, k_hp)

def _zpklp2hp ( z , p , k , wo = 1.0 ) : z = atleast_1d ( z ) p = atleast_1d ( p ) wo = float ( wo ) degree = _relative_degree ( z , p ) z_hp = ( wo / z ) p_hp = ( wo / p ) z_hp = append ( z_hp , zeros ( degree ) ) k_hp = ( k * real ( ( prod ( ( - z ) ) / prod ( ( - p ) ) ) ) ) return ( z_hp , p_hp , k_hp )
transform a lowpass filter prototype to a highpass filter .