How can I extract only the diagonal elements of a matrix product without computing the whole product matrix?팔로우 조회 수: 1 (최근 30일) Ranjan Sonalkar 2014년 6월 12일 추천 1 링크
Diagonal entriesLet N be a 3 × 3 normal matrix. We investigate the sets W k Π ( N ) = { ∏ l = 1 k ( UNU ) ll : U ∈ U ( 3 ) } , where U ( 3 ) is the group of 3 × 3 unitary matrices and 1 k 3. Geometric properties of these sets are studied, namely, star...
If a matrix D has nonzero elements dij only for i = j, it is said to be diagonal; a 3 × 3 example is D=(100020003). The rules of matrix multiplication cause all diagonal matrices (of the same size) to commute with each other. However, unless proportional to a unit matrix, diagon...
Suppose I want to calculate something like A*(Kron(B,eye(n))), where A is a large diagonal matrix whose main diagonal is also sparse. Is there a way to calculate this quickly? 채택된 답변 Matt J2022년 12월 23일
The result is an 8-by-8 block diagonal matrix. Repeat Matrix Elements Copy Code Copy Command Expand the size of a matrix by repeating elements. Create a 2-by-2 matrix of ones and a 2-by-3 matrix whose elements you want to repeat. Get A = [1 2 3; 4 5 6]; B = ones(...
If matrix A is lower triangular, (uplo = 'L'), these subroutines use only the data in the lower triangular portion of the array. In each case, the other portion of the array is altered during the computation, but restored before exit. The...
Index Expression for calculation Observation Wiener index ∑W(G) = 1 2 Di, j i, j Di,j represents off-diagonal elements of matrix which stands for the shortest distance in term on number of bonds between atom i and j ∑Valence connectivity index χ v(G) = 1 i,j viv j vi and vj...
We need to calculate the dot product for the diagonal entries of the result of the operation which we perform on the arrays.Calculating only the diagonal entries of the resultFor this purpose, we must use numpy.diag() while calculating the dot product of an array with t...
The inertia tensor is a positive definite matrix of the form: The first three elements of the Inertia vector are the moment of inertia, which are the diagonal elements of the inertia tensor. The last three elements are the product of inertia, which are the off-diagonal elements of the ...
The matrix D is the product of the matrices A and B if and only if, the elements of D are such that dij=∑k=1naikbkj. To achieve the product of two matrices, the matrices must be compatible. That is, the number of columns of matrix A must be equal to the number of rows of ma...