In the mathematical field of linear algebra and convex analysis, the numerical range or field of values of a complex n × n matrix A is the set
where x* denotes the Hermitian adjoint of the vector x.
In engineering, numerical ranges are used as a rough estimate of eigenvalues of A. Recently, generalizations of numerical range are used to study quantum computing.
A related concept is the numerical radius, which is the largest absolute values of the numbers in the numerical range, i.e.
r(A) is a norm.
Read more about Numerical Range: Properties, Generalisations, See Also
Famous quotes containing the words numerical and/or range:
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—Ralph Waldo Emerson (1803–1882)
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