Diagonal

Diagonal[m]

gives the list of elements on the leading diagonal of the matrix m.

Diagonal[m,k]

gives the elements on the k^(th) diagonal of m.

Details

  • Diagonal[m] works even if m is not a square matrix.
  • For positive k, Diagonal[m,k] gives diagonals above the leading diagonal. Diagonal[m,-k] gives diagonals below.

Examples

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Basic Examples  (3)

Give the diagonal elements of a matrix:

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Give diagonals one element above and below the leading diagonal:

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Give a diagonal of a nonsquare matrix:

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Neat Examples  (1)

See Also

DiagonalMatrix  Tr  Band  LowerTriangularize  UpperTriangularize

Introduced in 2007
(6.0)