Upper Triangular Matrix
TOPICS
A triangular matrix 
of the form
 |
(1) |
Written explicitly,
![U=[a_(11) a_(12) ... a_(1n); 0 a_(22) ... a_(2n); | | ... |; 0 0 ... a_(nn)].](https://mathworld.wolfram.com/images/equations/UpperTriangularMatrix/NumberedEquation2.svg) |
(2) |
A matrix 
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., 
for 
.
See also
Strictly Upper Triangular Matrix, Triangular Matrix, Lower Triangular Matrix
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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
Cite this as:
Weisstein, Eric W. "Upper Triangular Matrix." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/UpperTriangularMatrix.html