🚀 go-pugleaf

   I have to compute the determinant of a block pentadiagonal matrix, exactly
 a matrix look like :

              / A  B  C                 \
             |  B  A  B  C               |
             |  C  B  A  B  C            |
             |     C  B  A  B  C         |
             |        -------------      |
             |           -------------   |
             |           C  B  A  B  C   |
             |              C  B  A  B   |
              \                C  B  A  /

where    A is a pentadiagonal matrix
         B is a   tridiagonal matrix
         C is a      diagonal matrix

and besides A, B, C are commuting pairwise (i.e. AB = BA, AC = CA, BC = CB)


   In fact, it is easy to find a efficient method to compute the determinant
of the pentadiagonal matrix by Gauss elimination way. What i need is a formula
for computing the determinant of a block pentadiagonal matrix from the
determinant of each (commuting) element.


   Do you have an idea how to solve this problem ?


                Thank you for responding, (please email me)

                        Nicolas RATIER


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   |       L.A.A.S.   (France)         |
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   | Nicolas RATIER                    |
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