strictly lower triangular matrix

(data structure)

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

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

See also strictly upper triangular matrix, ragged matrix.

Note: For example

i ----

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

Author: PEB

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

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Entry modified 16 November 2016.
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Cite this as:
Paul E. Black, "strictly lower triangular matrix", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed. 16 November 2016. (accessed TODAY) Available from: