def lp2lp(b, a, wo=1.0):
 (a, b) = map(atleast_1d, (a, b))
 try:
  wo = float(wo)
 except TypeError:
  wo = float(wo[0])
 d = len(a)
 n = len(b)
 M = max((d, n))
 pwo = pow(wo, numpy.arange((M - 1), (-1), (-1)))
 start1 = max(((n - d), 0))
 start2 = max(((d - n), 0))
 b = ((b * pwo[start1]) / pwo[start2:])
 a = ((a * pwo[start1]) / pwo[start1:])
 return normalize(b, a)

def lp2lp ( b , a , wo = 1.0 ) : ( a , b ) = map ( atleast_1d , ( a , b ) ) try : wo = float ( wo ) except TypeError : wo = float ( wo [ 0 ] ) d = len ( a ) n = len ( b ) M = max ( ( d , n ) ) pwo = pow ( wo , numpy . arange ( ( M - 1 ) , ( - 1 ) , ( - 1 ) ) ) start1 = max ( ( ( n - d ) , 0 ) ) start2 = max ( ( ( d - n ) , 0 ) ) b = ( ( b * pwo [ start1 ] ) / pwo [ start2 : ] ) a = ( ( a * pwo [ start1 ] ) / pwo [ start1 : ] ) return normalize ( b , a )
transform a lowpass filter prototype to a different frequency .