> 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):
> Masssenmatrix:=Int(rho*evalm(J),V);

  Masssenmatrix :=

          /     [      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 -> 1-3*xi^2+2*xi^3;

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

> N[2]:=xi ->l*xi*(1-xi)^2;

                                                2
                     N[2] := xi -> l xi (1 - xi)

> N[3]:=xi -> xi^2*(3-2*xi);

                                     2
                     N[3] := xi -> xi  (3 - 2 xi)

> N[4]:=xi -> -l*xi^2*(1-xi);

                                       2
                    N[4] := xi -> -l xi  (1 - xi)

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

                   [  13      11 l                 13 l]
                   [  --      ----      9/70     - ----]
                   [  35      210                  420 ]
                   [                                   ]
                   [            2                   2  ]
                   [ 11 l      l        13 l       l   ]
                   [ ----      ---      ----     - --- ]
                   [ 210       105      420        140 ]
              p := [                                   ]
                   [          13 l       13        11 l]
                   [ 9/70     ----       --      - ----]
                   [          420        35        210 ]
                   [                                   ]
                   [             2                 2   ]
                   [  13 l      l        11 l     l    ]
                   [- ----    - ---    - ----     ---  ]
                   [  420       140      210      105  ]

> Massenmatrix:=(rho*A*l)/420*evalm(420*p);

                                 [ 156     22 l      54      -13 l]
                                 [                                ]
                                 [            2                  2]
                                 [22 l     4 l      13 l     -3 l ]
   Massenmatrix := 1/420 rho A l [                                ]
                                 [ 54      13 l      156     -22 l]
                                 [                                ]
                                 [             2                2 ]
                                 [-13 l    -3 l     -22 l    4 l  ]

> 
> 
