Expand description
Numeric threshold incomplete Cholesky (ICT).
Left-looking column Cholesky with dual dropping (a drop tolerance and a per-column fill budget), restricted to the lower triangle. Because the fill pattern depends on the matrix values, there is no symbolic phase — the factor is rebuilt in full each time (reusing buffer capacity).
To find, when forming column j, every earlier column k that has a stored
entry in row j, we keep the standard linked-list of active columns: bucket
head[j] chains the columns whose current cursor points at row j.
Structs§
- Ict
- Numeric ICT factor of a Hermitian positive-definite CSC matrix
A.