Not to be confused with a triangular array, a related concept.
For the rings, see triangular matrix ring.
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 are zero. Similarly, a square matrix is called upper triangular if all the entries below the main diagonal are zero.
Because matrix equations with triangular matrices are easier to solve, they are very important in numerical analysis. By the LU decomposition algorithm, an invertible matrix may be written as the product of a lower triangular matrix L and an upper triangular matrix U if and only if all its leading principal minors are non-zero.
In mathematics, a triangularmatrix is a special kind of square matrix. A square matrix is called lower triangular if all the entries above the main diagonal...
decomposition. The LU decomposition factorizes a matrix into a lower triangularmatrix L and an upper triangularmatrix U. The systems L ( U x ) = b {\displaystyle...
diagonal matrix. If all entries below (resp above) the main diagonal are zero, A {\displaystyle A} is called an upper (resp lower) triangularmatrix. The...
the Crout matrix decomposition is an LU decomposition which decomposes a matrix into a lower triangularmatrix (L), an upper triangularmatrix (U) and,...
factorization, is a decomposition of a matrix A into a product A = QR of an orthonormal matrix Q and an upper triangularmatrix R. QR decomposition is often used...
positive definiteness of a symmetric real matrix. Namely, the matrix is reduced to an upper triangularmatrix by using elementary row operations, as in...
algebra, a Hessenberg matrix is a special kind of square matrix, one that is "almost" triangular. To be exact, an upper Hessenberg matrix has zero entries...
In linear algebra, a symmetric matrix is a square matrix that is equal to its transpose. Formally, A is symmetric ⟺ A = A T . {\displaystyle A{\text{...
of these vectors. A matrix whose elements above the main diagonal are all zero is called a lower triangularmatrix, while a matrix whose elements below...
Schur, is a matrix decomposition. It allows one to write an arbitrary complex square matrix as unitarily equivalent to an upper triangularmatrix whose diagonal...
In algebra, a triangularmatrix ring, also called a triangular ring, is a ring constructed from two rings and a bimodule. If T {\displaystyle T} and U...
of a triangularmatrix are precisely its eigenvalues (see Triangularmatrix#Properties). An n × n matrix A is diagonalizable if there is a matrix V and...
possible for a real or complex matrix to have all real eigenvalues without being Hermitian. For example, a real triangularmatrix has its eigenvalues along...
algebra, the characteristic polynomial of a square matrix is a polynomial which is invariant under matrix similarity and has the eigenvalues as roots. It...
In mathematics, particularly matrix theory, a band matrix or banded matrix is a sparse matrix whose non-zero entries are confined to a diagonal band, comprising...
and a matrix in row echelon form is (weakly) upper triangular. Thus, the row echelon form can be viewed as a generalization of upper triangular form for...
decomposition of a Hermitian, positive-definite matrix into the product of a lower triangularmatrix and its conjugate transpose, which is useful for...
to another row. Using these operations, a matrix can always be transformed into an upper triangularmatrix, and in fact one that is in row echelon form...
triangularmatrix with zeros along the main diagonal is nilpotent, with index ≤ n {\displaystyle \leq n} [citation needed]. For example, the matrix B...
perform a QR decomposition, writing the matrix as a product of an orthogonal matrix and an upper triangularmatrix, multiply the factors in the reverse order...
perturbation theory also leads to matrix eigenvalue problem for degenerate states. Defective matrix Scaling (geometry) Triangularmatrix Semisimple operator Diagonalizable...
triangular Toeplitz matrices and C {\displaystyle C} is a strictly lower triangularmatrix. The convolution operation can be constructed as a matrix multiplication...
from above) yield an upper triangularmatrix in order to compute the QR decomposition. In order to form the desired matrix, zeroing elements (2,1) and...
square matrix. The determinant of a matrix A is commonly denoted det(A), det A, or |A|. Its value characterizes some properties of the matrix and the...
{\displaystyle T} is a triangularmatrix. For a matrix A {\displaystyle A} of rank r {\displaystyle r} , the triangularmatrix T {\displaystyle T} can...
_{i}{\big (}|a_{ii}|{\big )}}}} recalling that the eigenvalues of any triangularmatrix are simply the diagonal entries. The condition number computed with...