#!/usr/bin/python

# 11.6

from zpowk import zpowk

from polyfuncs import polmul, poladd

from tfvar import tfvar

def cl(A,dA,B,dB,C,dC,k,S,dS,R,dR,int1):

    """

    int>=1 means integrated noise and control law:

    delta u = - (S/R)y

    Evaluates the closed loop transfer function and 

    variances of input and output

    """

    zk, dzk = zpowk(k)

    BS, dBS = polmul(B,dB,S,dS)

    zBS, dzBS = polmul(zk,dzk,BS,dBS)

    RA, dRA = polmul(R,dR,A,dA)

    if int1>=1:

        RA, dRA = polmul(RA, dRA, [1, -1], 1)

    D, dD = poladd(RA, dRA, zBS, dzBS)

    D = D.squeeze()

    Ny, dNy = polmul(C,dC,R,dR)

    Nu, dNu = polmul(C,dC,S,dS)

    Nu, dNu, Du, dDu, uvar = tfvar(Nu, dNu, D, dD)

    Ny, dNy, Dy, dDy, yvar = tfvar(Ny, dNy, D, dD)

    return Nu, dNu, Du, dDu, Ny, dNy, Dy, dDy, yvar, uvar