Definition: A matrix that is only defined at (i,j) when i ≥ j.
Generalization (I am a kind of ...)
Specialization (... is a kind of me.)
strictly lower triangular matrix.
See also upper triangular matrix, ragged matrix.
j i 1 - - - 7 7 - - 1 0 1 - 1 9 5 4
It may be more compactly represented in an array by storing entry (i,j) in location i(i-1)/2 + j (one-based indexing).
If you have suggestions, corrections, or comments, please get in touch with Paul Black.
Entry modified 17 December 2004.
HTML page formatted Mon Feb 2 13:10:39 2015.
Cite this as:
Paul E. Black, "lower triangular matrix", in Dictionary of Algorithms and Data Structures [online], Vreda Pieterse and Paul E. Black, eds. 17 December 2004. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/lowerTriangularMatrix.html