- References
In mathematics, the pseudospectrum of an operator is a set containing the spectrum of the operator and the numbers that are "almost" eigenvalues. Knowledge of the pseudospectrum can be particularly useful for understanding non-normal operators and their eigenfunctions.
The ε-pseudospectrum of a matrix A consists of all eigenvalues of matrices which are ε-close to A:[1]
Numerical algorithms which calculate the eigenvalues of a matrix give only approximate results due to rounding and other errors. These errors can be described with the matrix E.
References
1. ^{{cite book|last1=Hogben|first1=Leslie|title=Handbook of Linear Algebra, Second Edition|date=2013|publisher=CRC Press|isbn=9781466507296|page=23-1|url=https://books.google.com/books?id=Er7MBQAAQBAJ&pg=SA23-PA18&dq=pseudospectrum&hl=en&sa=X&ved=0ahUKEwj11Ke34ZTWAhXJgFQKHbtZBbkQ6AEIQzAE#v=onepage&q=pseudospectrum&f=false|accessdate=8 September 2017|language=en}}
- Pseudospectra Gateway / Embree and Trefethen
2 : Numerical linear algebra|Spectral theory
- Joo Seng
- Joosep
- Joo Soon-lan
- Joos, Stefan
- Joost A. Businger
- Joost Augusteijn
- Joost Businger
- Joost Caen
- Jooste
- Joost Halbertsma
- Joost Hiddes Halbertsma
- Joost Kooistra
- Joost Leemhuis
- Joost Meendering
- Joost-Pieter Katoen
- Joost R. Hiltermann
- Joost Rietdijk
- Joost R. Ritman
- Joost Röben
- Joost Theo Sylvio Yussef Abdelgalil Dowib
- Joost Vander Auwera
- Joost Van Der Burg
- Joost Van der Burg
- Joost van der Burg
- Joost van Hemert