Linear systems
Solve Ax=b through direct and iterative methods while tracking sparsity, scale and structure.
Subject
Purpose
Linear systems, eigenproblems and matrix factorizations studied through algorithms, conditioning, stability and finite-precision computation.
Structure
Definitions → structures → relations → proof → application
Numerical linear algebra asks not only whether a matrix problem has a solution, but whether that solution can be computed accurately and efficiently on real hardware.
Solve Ax=b through direct and iterative methods while tracking sparsity, scale and structure.
Use LU, QR, Cholesky and related decompositions to expose stable computational pathways.
Measure how sensitive a problem's exact solution is to perturbations in data.
Analyze how an algorithm amplifies rounding and approximation error beyond the underlying problem sensitivity.
Compute dominant modes, ranks and low-dimensional structure using algorithms suited to dense or sparse matrices.
conditioning ≠ algorithm stability
exact arithmetic ≠ floating-point arithmetic
small residual ≠ small solution error
How can a numerically stable algorithm still produce an inaccurate answer?
Why is QR often preferred to normal equations in least squares?
How do matrix structure and sparsity change algorithm choice?
Report residuals, conditioning and convergence behavior; numerical agreement alone is weak evidence when the problem is ill-conditioned.