Numerical Methods - Overview
Introduction
Overview of computational aspects of linear algebra: norms, conditioning, and iterative methods.
Key Concepts
Matrix Norms
- Vector norms: ||x||₁, ||x||₂, ||x||∞
- Matrix norms
- Induced norms
- Frobenius norm
Condition Numbers
- κ(A) = ||A|| ||A⁻¹||
- Ill-conditioned vs well-conditioned matrices
- Impact on numerical accuracy
- Relationship to eigenvalues
Eigenvalue Computation
- Power method
- QR algorithm
- Jacobi method
- Applications to large-scale problems
Iterative Methods
- Jacobi iteration
- Gauss-Seidel
- Conjugate gradient
- When to use iterative vs direct methods
Applications
- Large-scale linear systems
- Sparse matrices
- Machine learning optimization
- Scientific computing
References
- Strang Chapter 7
- Deep Dive