Examples of using Triangular matrix in English and their translations into Russian
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A normal triangular matrix is diagonal.
If all entries of A below the main diagonal are zero,A is called an upper triangular matrix.
Output data: the lower triangular matrix[math]L[/math] whose elements are denoted by[math]l_{ij}/math.
The first fragment describes the forward substitution, namely,the solution of the SLAE with a lower triangular matrix[math]L\vec{y}\vec{b}[/math] Fig.3.
For example, a real triangular matrix has its eigenvalues along its diagonal, but in general is not symmetric.
A similar procedure of solving a linear system with a lower triangular matrix is called the forward substitution see 1.
These methods use triangular matrix with sums in rows tending to zero and with some conditions on difference of coefficients.
The second fragment describes the back substitution, namely,the solution of the SLAE with an upper triangular matrix[math]U\vec{x}\vec{y}[/math] Fig.4.
Output data: upper triangular matrix[math]R[/math], unitary(or orthogonal) matrix[math]Q[/math] stored as the product of rotations.
Compute the Cholesky decomposition[math]T_i-\tau 2_iI=B_i TB_i,[/math] where[math]B_i[/math]is an upper triangular matrix with a positive diagonal.
Explicit methods have a strictly lower triangular matrix A, which implies that det(I- zA) 1 and that the stability function is a polynomial.
At the k-th step(starting with k 0), we compute the QR decomposition Ak=QkRk where Qk is an orthogonal matrix(i.e., QT Q-1) andRk is an upper triangular matrix.
Nevertheless, the structure of the forward substitution for a nonsingular left triangular matrix is virtually identical to the structure of the back substitution.
Because the eigenvalues of a triangular matrix are its diagonal elements, for general matrices there is no finite method like gaussian elimination to convert a matrix to triangular form while preserving eigenvalues.
Backward substitution is a procedure of solving a system of linear algebraic equations[math]Ux y[/math], where[math]U[/math]is an upper triangular matrix whose diagonal elements are not equal to zero.
These include: Since the determinant of a triangular matrix is the product of its diagonal entries, if T is triangular, then det( λ I- T)∏ i( λ- T i i){\displaystyle\textstyle \det(\lambda I-T)=\prod_{i}\lambda-T_{ii.
Similarly, the QR algorithm is used to compute the eigenvalues of any given matrix, which are the diagonal entries of the upper triangular matrix of the Schur decomposition.
In order to implement the backward substitution algorithm for a linear system with an upper triangular matrix of order[math]n[/math], a parallel version of this algorithm should perform the following layers of operations.
The following number of operations should be performed for the backward substitution in the case of solving a linear system with an upper triangular matrix of order[math]n[/math] using a serial most fast algorithm.
Using these operations,any matrix can be transformed to a lower(or upper) triangular matrix, and for such matrices the determinant equals the product of the entries on the main diagonal; this provides a method to calculate the determinant of any matrix. .
Finding the decomposition of a matrix A of the form[math]A QR[/math], where[math]Q[/math]is a unitary matrix and[math]R[/math] is an upper triangular matrix[1], is an important stage in solving certain more complex problems.
From this it is easily seen that all three matrices have determinant 1, as the determinant of a triangular matrix is simply the product of its diagonal elements, which are all 1 for both Ln and Un.
Reasoning in this way, Minkowski showed that(assuming the truth of his conjecture)every critical lattice has a basis that can be expressed as a triangular matrix, with ones on its main diagonal and numbers less than one away from the diagonal.
It was also noted in[1] that, in the literature,back substitution is usually regarded as solving a SLAE with a right triangular matrix, whereas the solution of left triangular systems is called the forward substitution.
Solving linear systems with complex triangular matrices.
This test stores both triangular matrices in the corresponding portions of the matrix[math]A/math.
Methods for solving block triangular matrices.
Solving linear systems with block bordered triangular matrices.
In the GL(3, 2) representation,a Sylow 2-subgroup consists of the upper triangular matrices.
For example, in the group GLn(n x n invertible matrices), the subgroup of invertible upper triangular matrices is a Borel subgroup.