In linear algebra, a Hilbert matrix, introduced by Hilbert (1894), is a square matrix with entries being the unit fractions
For example, this is the 5 × 5 Hilbert matrix:
The entries can also be defined by the integral
that is, as a Gramian matrix for powers of x. It arises in the least squares approximation of arbitrary functions by polynomials.
The Hilbert matrices are canonical examples of ill-conditioned matrices, being notoriously difficult to use in numerical computation. For example, the 2-norm condition number of the matrix above is about 4.8×105.
In linear algebra, a Hilbertmatrix, introduced by Hilbert (1894), is a square matrix with entries being the unit fractions H i j = 1 i + j − 1 . {\displaystyle...
this formulation is used is in Hilbert spaces. The finite-dimensional spectral theorem says that any symmetric matrix whose entries are real can be diagonalized...
sequences (they contain distinct elements). The Hilbertmatrix is a special case of the Cauchy matrix, where x i − y j = i + j − 1. {\displaystyle x_{i}-y_{j}=i+j-1...
In mathematics, Hilbert spaces (named after David Hilbert) allow the methods of linear algebra and calculus to be generalized from (finite-dimensional)...
{\displaystyle T} up to sign. The Hilbertmatrix is an example of a Hankel matrix. The determinant of a Hankel matrix is called a catalecticant. Given...
norm on the matrix. Numerical methods for linear least squares Numerical stability Hilbertmatrix Ill-posed problem Singular value Wilson matrix Belsley,...
{\displaystyle |1\rangle } in a two-dimensional Hilbert space, then the density operator is represented by the matrix ( ρ i j ) = ( ρ 00 ρ 01 ρ 10 ρ 11 ) = (...
Orthogonalization Parallelogram law Normal matrix, normal operator Orthogonal matrix Unitary matrix Semi-Hilbert space Diagonal matrix Eigenvector, eigenvalue, eigenfunction...
a Hilbertmatrix. It has the unusual property that all elements in its inverse matrix are integers. Similarly, Richardson (2001) defined a matrix whose...
result about when a linear operator or matrix can be diagonalized (that is, represented as a diagonal matrix in some basis). This is extremely useful...
square root of a matrix extends the notion of square root from numbers to matrices. A matrix B is said to be a square root of A if the matrix product BB is...
such norms are referred to as matrix norms. Matrix norms differ from vector norms in that they must also interact with matrix multiplication. Given a field...
on finite-dimensional Hilbert spaces, so the notion of a unitary operator is a generalization of the notion of a unitary matrix. Orthogonal matrices are...
algebra, a matrix decomposition or matrix factorization is a factorization of a matrix into a product of matrices. There are many different matrix decompositions;...
In mathematics, a triangular matrix is a special kind of square matrix. A square matrix is called lower triangular if all the entries above the main diagonal...
linear algebra, a square matrix A {\displaystyle A} is called diagonalizable or non-defective if it is similar to a diagonal matrix. That is, if there exists...
compact operator on Hilbert space is an extension of the concept of a matrix acting on a finite-dimensional vector space; in Hilbert space, compact operators...
matrices used in mathematics, science and engineering. A matrix (plural matrices, or less commonly matrixes) is a rectangular array of numbers called entries...
transformation from Hilbert space C n {\displaystyle \mathbb {C} ^{n}} to C m , {\displaystyle \mathbb {C} ^{m},} then the matrix A H {\displaystyle \mathbf...
analysis (a branch of mathematics), a reproducing kernel Hilbert space (RKHS) is a Hilbert space of functions in which point evaluation is a continuous...
state that has been found is projected into the Hilbert subspace for each block using a density matrix, hence the name. Thus, the relevant states for each...
In mathematics, a complex square matrix A is normal if it commutes with its conjugate transpose A*: A normal ⟺ A ∗ A = A A ∗ . {\displaystyle A{\text{...
In mathematics, a symmetric matrix M {\displaystyle M} with real entries is positive-definite if the real number z T M z {\displaystyle z^{\operatorname...