Upper Triangular Matrix
A triangular matrix U of the form
Written explicitly,
![画像: U=[a_(11) a_(12) ... a_(1n); 0 a_(22) ... a_(2n); | | ... |; 0 0 ... a_(nn)].](/index.cgi/contrast/https://mathworld.wolfram.com/images/equations/UpperTriangularMatrix/NumberedEquation2.svg){kind=link}
A matrix m can be tested to determine if it is upper triangular in the Wolfram Language using UpperTriangularMatrixQ [m].
A strictly upper triangular matrix is an upper triangular matrix having 0s along the diagonal as well, i.e., a_(ij)=0 for i>=j.
See also
Strictly Upper Triangular Matrix, Triangular Matrix, Lower Triangular MatrixExplore with Wolfram|Alpha
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References
Ayres, F. Jr. Schaum's Outline of Theory and Problems of Matrices. New York: Schaum, p. 10, 1962.Referenced on Wolfram|Alpha
Upper Triangular MatrixCite this as:
Weisstein, Eric W. "Upper Triangular Matrix." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/UpperTriangularMatrix.html