FF_LUComputation Class Reference

LU decomposition over a domain using fraction-free Gaussian elimination. More...

#include <fractionfreeLU.hpp>

Static Public Member Functions
static M2_arrayintOrNull	DO (MutableMatrix *M)

Private Member Functions
	FF_LUComputation (MutableMatrix *M)
	~FF_LUComputation ()
bool	choose_pivot_column (int lo, int hi, int &result)
void	do_pivots (int lo, int hi, int pivot_col)
bool	calc ()
M2_arrayint	get_column_permutation ()

Private Attributes
const Ring *	R
MutableMatrix *	M
int *	col_perm
bool *	need_div
int	pivot_col
ring_elem	lastpivot
ring_elem	pivot

Detailed Description

LU decomposition over a domain using fraction-free Gaussian elimination.

Note

AI-generated documentation. Verify against the source before relying on it.

The classical Bareiss-style algorithm: at each step, the new entry is (pivot * a - factor * b) / lastpivot, where the division is exact because the ring is a domain. Tracks col_perm for the column permutation and need_div[i] for which columns still need the trailing division. Used by the engine wherever an integer-coefficient LU is needed without introducing fractions.

Definition at line 53 of file fractionfreeLU.hpp.

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The documentation for this class was generated from the following files:

• Macaulay2/e/fractionfreeLU.hpp
• Macaulay2/e/fractionfreeLU.cpp