nums.core.linalg module
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nums.core.linalg.
inv_uppertri
(app, X)[source] Distributed algorithm for the inversion of an Upper Triangular Matrix. We use the method and notation described in - https://www.cs.utexas.edu/users/flame/pubs/siam_spd.pdf.
The upper-triangular matrix X is partitioned as follows:
_________________ | R_00 ‖ R_01 | R_02 | | R_TL | R_TR | |==========================|
- X = R -> |---------------| -> | 0 ‖ R_11 | R_12 |
- 0 | R_BR | |--------------------------|
- ⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻ | 0 ‖ 0 | R_22 |
⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻
where the double lines represent the boundaries between R_TL, R_TR, and R_BR.