Jordan block size

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I was wondering about the size of the Jordan blocks of the following matrix.



$$beginbmatrix
0 & 1 & 0\
0 & 0 & 1\
0 & 0 & 0
endbmatrix$$



I know that Jordan blocks have $1$'s on the superdiagonal. So are these $3$ blocks of size $1 times 1$ or is this one block of size $3 times 3$? I'm not sure how to tell the difference. Thanks in advance.







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    up vote
    3
    down vote

    favorite












    I was wondering about the size of the Jordan blocks of the following matrix.



    $$beginbmatrix
    0 & 1 & 0\
    0 & 0 & 1\
    0 & 0 & 0
    endbmatrix$$



    I know that Jordan blocks have $1$'s on the superdiagonal. So are these $3$ blocks of size $1 times 1$ or is this one block of size $3 times 3$? I'm not sure how to tell the difference. Thanks in advance.







    share|cite|improve this question























      up vote
      3
      down vote

      favorite









      up vote
      3
      down vote

      favorite











      I was wondering about the size of the Jordan blocks of the following matrix.



      $$beginbmatrix
      0 & 1 & 0\
      0 & 0 & 1\
      0 & 0 & 0
      endbmatrix$$



      I know that Jordan blocks have $1$'s on the superdiagonal. So are these $3$ blocks of size $1 times 1$ or is this one block of size $3 times 3$? I'm not sure how to tell the difference. Thanks in advance.







      share|cite|improve this question













      I was wondering about the size of the Jordan blocks of the following matrix.



      $$beginbmatrix
      0 & 1 & 0\
      0 & 0 & 1\
      0 & 0 & 0
      endbmatrix$$



      I know that Jordan blocks have $1$'s on the superdiagonal. So are these $3$ blocks of size $1 times 1$ or is this one block of size $3 times 3$? I'm not sure how to tell the difference. Thanks in advance.









      share|cite|improve this question












      share|cite|improve this question




      share|cite|improve this question








      edited Jul 27 at 20:02









      Rodrigo de Azevedo

      12.6k41751




      12.6k41751









      asked Jul 24 at 5:19









      user463102

      1268




      1268




















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          If this was three 1×1 blocks, there wouldn't be any non-zero values off the main diagonal (because a 1×1 block is just the eigenvalue itself), so this must be one 3×3 block with corresponding eigenvalue zero.






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            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes








            up vote
            3
            down vote



            accepted










            If this was three 1×1 blocks, there wouldn't be any non-zero values off the main diagonal (because a 1×1 block is just the eigenvalue itself), so this must be one 3×3 block with corresponding eigenvalue zero.






            share|cite|improve this answer

























              up vote
              3
              down vote



              accepted










              If this was three 1×1 blocks, there wouldn't be any non-zero values off the main diagonal (because a 1×1 block is just the eigenvalue itself), so this must be one 3×3 block with corresponding eigenvalue zero.






              share|cite|improve this answer























                up vote
                3
                down vote



                accepted







                up vote
                3
                down vote



                accepted






                If this was three 1×1 blocks, there wouldn't be any non-zero values off the main diagonal (because a 1×1 block is just the eigenvalue itself), so this must be one 3×3 block with corresponding eigenvalue zero.






                share|cite|improve this answer













                If this was three 1×1 blocks, there wouldn't be any non-zero values off the main diagonal (because a 1×1 block is just the eigenvalue itself), so this must be one 3×3 block with corresponding eigenvalue zero.







                share|cite|improve this answer













                share|cite|improve this answer



                share|cite|improve this answer











                answered Jul 24 at 5:32









                Parcly Taxel

                33.5k136588




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