NIST

lower triangular matrix

(data structure)

Definition: A matrix that is only defined at (i,j) when i ≥ j.

Generalization (I am a kind of ...)
matrix.

Specialization (... is a kind of me.)
strictly lower triangular matrix.

See also upper triangular matrix, ragged matrix.

Note: For example

j
i 1---
77--
101-
1954

It may be more compactly represented in an array by storing entry (i,j) in location i(i-1)/2 + j (1-based indexing).

Author: PEB

Implementation

(Fortran)
Go to the Dictionary of Algorithms and Data Structures home page.

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Entry modified 16 November 2016.
HTML page formatted Wed Mar 13 12:42:46 2019.

Cite this as:
Paul E. Black, "lower triangular matrix", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed. 16 November 2016. (accessed TODAY) Available from: https://www.nist.gov/dads/HTML/lowerTriangularMatrix.html