Exchange matrix

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In mathematics, especially linear algebra, the exchange matrices (also called the reversal matrix, backward identity, or standard involutory permutation) are special cases of permutation matrices, where the 1 elements reside on the antidiagonal and all other elements are zero. In other words, they are 'row-reversed' or 'column-reversed' versions of the identity matrix. [1]

Contents

Definition

If J is an n × n exchange matrix, then the elements of J are

Properties

its eigenvalues are 1 (with multiplicity ) and -1 (with multiplicity ).

Relationships

See also

References

  1. Horn, Roger A.; Johnson, Charles R. (2012), "§0.9.5.1 n-by-n reversal matrix", Matrix Analysis (2nd ed.), Cambridge University Press, p. 33, ISBN   978-1-139-78888-5 .