> with(linalg):
Warning, the protected names norm and trace have been redefined and
unprotected

> Formfunktionen:=matrix(1,4,[N[1],N[2],N[3],N[4]]);

           Formfunktionen := [N[1]    N[2]    N[3]    N[4]]

> J:=multiply(transpose(Formfunktionen),Formfunktionen):
> Massenmatrix:=Int(rho*evalm(J),V);

  Massenmatrix :=

          /     [      2                                         ]
         |      [  N[1]       N[1] N[2]    N[1] N[3]    N[1] N[4]]
         |      [                                                ]
         |      [                   2                            ]
         |      [N[1] N[2]      N[2]       N[2] N[3]    N[2] N[4]]
         |  rho [                                                ] dV
         |      [                                2               ]
         |      [N[1] N[3]    N[2] N[3]      N[3]       N[3] N[4]]
         |      [                                                ]
         |      [                                             2  ]
        /       [N[1] N[4]    N[2] N[4]    N[3] N[4]      N[4]   ]

> N[1]:=xi -> 1-(11/2)*xi+9*xi^2-(9/2)*xi^3;

                                             2         3
             N[1] := xi -> 1 - 11/2 xi + 9 xi  - 9/2 xi

> N[2]:=xi -> 9*xi-(45/2)*xi^2+(27/2)*xi^3;

                                           2          3
               N[2] := xi -> 9 xi - 45/2 xi  + 27/2 xi

> N[3]:=xi -> -(9/2)*xi+18*xi^2-(27/2)*xi^3;

                                           2          3
              N[3] := xi -> -9/2 xi + 18 xi  - 27/2 xi

> N[4]:=xi -> xi-(9/2)*xi^2+(9/2)*xi^3;

                                          2         3
                 N[4] := xi -> xi - 9/2 xi  + 9/2 xi

> p:=map(int,J(xi),xi=0..1);

                      [         33     -3      19  ]
                      [8/105    ---    ---    ---- ]
                      [         560    140    1680 ]
                      [                            ]
                      [ 33      27     -27     -3  ]
                      [ ---     --     ---     --- ]
                      [ 560     70     560     140 ]
                 p := [                            ]
                      [ -3      -27    27      33  ]
                      [ ---     ---    --      --- ]
                      [ 140     560    70      560 ]
                      [                            ]
                      [ 19      -3     33          ]
                      [----     ---    ---    8/105]
                      [1680     140    560         ]

> Massenmatrix:=(rho*A*l)/1680*evalm(1680*p);

                                     [128     99    -36     19]
                                     [                        ]
                                     [ 99    648    -81    -36]
      Massenmatrix := 1/1680 rho A l [                        ]
                                     [-36    -81    648     99]
                                     [                        ]
                                     [ 19    -36     99    128]

> 
> 
