matrix exponntial



On 12 Nov 2001, Matthias Bechmann wrote:

>when i tried myself i.e.:   exp(%I*I_z);
>
>                    with:   I_z:matrix([1,0],[0,-1]);
>
>                   i get:   [   %I	       ]
>                            [ %E	  1    ]
>                            [	          - %I ]
>                            [  1        %E     ]
>
>              but expect:   [   %I	       ]
>                            [ %E	  0    ]
>                            [	          - %I ]
>                            [  0        %E     ]

I tried this with Matlab:
>> iz=[1 0; 0 -1]

iz =

     1     0
     0    -1

>> exp(i^iz)

ans =

  Column 1

           0.54030230586814 +     0.841470984807897i
                          1

  Column 2

                          1
           0.54030230586814 -     0.841470984807897i


...so i got the same result what Maxima returns. Looks like
Maxima is correct unless also Matlab has the same bug.