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A nearly-mlogn time solver for SDD linear systems

3 Pith papers cite this work. Polarity classification is still indexing.

3 Pith papers citing it
abstract

We present an improved algorithm for solving symmetrically diagonally dominant linear systems. On input of an $n\times n$ symmetric diagonally dominant matrix $A$ with $m$ non-zero entries and a vector $b$ such that $A\bar{x} = b$ for some (unknown) vector $\bar{x}$, our algorithm computes a vector $x$ such that $||{x}-\bar{x}||_A < \epsilon ||\bar{x}||_A $ {$||\cdot||_A$ denotes the A-norm} in time $${\tilde O}(m\log n \log (1/\epsilon)).$$ The solver utilizes in a standard way a `preconditioning' chain of progressively sparser graphs. To claim the faster running time we make a two-fold improvement in the algorithm for constructing the chain. The new chain exploits previously unknown properties of the graph sparsification algorithm given in [Koutis,Miller,Peng, FOCS 2010], allowing for stronger preconditioning properties. We also present an algorithm of independent interest that constructs nearly-tight low-stretch spanning trees in time $\tilde{O}(m\log{n})$, a factor of $O(\log{n})$ faster than the algorithm in [Abraham,Bartal,Neiman, FOCS 2008]. This speedup directly reflects on the construction time of the preconditioning chain.

fields

cs.LG 2 cs.DS 1

years

2026 2 2019 1

verdicts

UNVERDICTED 3

representative citing papers

Flows in Almost Linear Time via Adaptive Preconditioning

cs.DS · 2019-06-25 · unverdicted · novelty 7.0

Algorithms achieve almost-linear time for ℓ_p-norm flow and dual regression problems on unit-weighted graphs for a range of p, plus applications to max-flow and total variation.

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Showing 3 of 3 citing papers.