def METHOD_NAME(frame, ch, blk, C):
    global X
    M = frame.nr_subbands
    L = 10 * M
    M2 = 2*M
    L2 = 2*L
    Z = np.zeros(L)
    Y = np.zeros(M2)
    W = np.zeros(shape=(M, M2))
    S = np.zeros(M)
    for i in range(L-1, M-1, -1):
        X[ch][i] = X[ch][i-M]
    for i in range(M-1, -1, -1):
        X[ch][i] = frame.EX[M-1-i]
    for i in range(L):
        Z[i] = X[ch][i] * C[i]
    for i in range(M2):
        for k in range(5):
            Y[i] += Z[i+k*M2]
    for i in range(M):
        for k in range(M2):
            W[i][k] = np.cos((i+0.5)*(k-M/2)*np.pi/M)
            S[i] += W[i][k] * Y[k]
    for sb in range(M):
        frame.sb_sample[blk][ch][sb] = S[sb]