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118                                                        Chapter 3

              Consider any vector in the space  can  also be represented as the linear
           combination of Wavelet basis as described below. Note that orthonormal
           basis

              w1=  (1/sqrt(8)) [1 1 1 1 1 1 1 1] T
              w2=  (1/sqrt(8)) [1 1 1 1 -1 -1 -1 -1] T
              w3= (1/sqrt(4)) [1 1 -1 -1 0 0 0 0] T
              w4= (1/sqrt(4)) [0 0 0 0 1 1 -1 -1] T
              w5=  (1/sqrt(2)) [1 -1 0 0 0 0 0 0] T
              w6= (1/sqrt(2)) [0 0 1 -1 0 0 0 0] T
              w7= (1/sqrt(2)) [0 0 0 0 1 -1 0 0] T
              w8= (1/sqrt(2)) [0 0 0 0 0 0 1 -1] T

              As described in the section 11.3 the transformation matrix which
           converts the co-efficient of the basis u1,u2,…u8 into the co-efficient of the
           basis w1, w2, w3,…w8 for the particular vector is computed and is displayed
           below.

            0.3536    0.3536     0.3536       0.3536    0.3536    0.3536     0.3536     0.3536
            0.3536    0.3536     0.3536       0.3536    -0.3536    -0.3536     -0.3536    -0.3536
            0.5000    0.5000     -0.5000      -0.5000     0   0   0     0
            0       0        0         0       0.5000    0.5000    -0.5000    -0.5000
            0.7071   - 0.7071     0    0       0       0       0        0
            0       0        0.7071      0.7071    0   0       0        0
            0       0        0         0       0.7071    0.7071    0    0
            0       0        0         0       0       0       0.7071     0.7071


              Note that the transformation matrix consists of the wavelet basis arranged
           row wise.

           12.      SYSTEM STABILITY TEST USING
                    EIGEN VALUES


           Input signal and output signal of the  system are usually related with
           differential  equation. The output signal is solved using the eigen
           decomposition as described in the section 9. The general expression of the
           output signal is of the form output (t)=c1 e λ1 t    E 1 +c2 e λ2 t   E 2 + c3 e λ3 t    E 3.
           where  λ1,  λ2 and  λ3 are the eigen values. E 1, E2 and E3 are  the eigen
           vectors of the matrix described in the section 9.
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