Jacobi Iteration Solver

Parallel Ax=b iteration

CalculatorsFreeNo Signup
4.4(325 reviews)
All Tools

Loading tool...

About Jacobi Iteration Solver

A Jacobi iterative solver for linear systems. Simultaneously updates all unknowns using values from the previous iteration. Shows iteration table with convergence. Checks diagonal dominance. Naturally parallelizable. Select from preset systems. All calculations are client-side.

Jacobi Iteration Solver Features

  • Parallel update
  • Iteration table
  • Diag dominance
  • Convergence
  • Presets
Jacobi iteration: xᵢ^(k+1) = (bᵢ − Σⱼ≠ᵢ aᵢⱼxⱼ^(k))/aᵢᵢ. All components updated simultaneously using previous iteration. Naturally parallel. Converges for diagonally dominant matrices. Decomposition: A = D + L + U, iteration: x^(k+1) = D⁻¹(b − (L+U)x^(k)).

How to Use

Set up the system:

  • Matrix A: Coefficients
  • Vector b: Right-hand side
  • Output: Solution + iterations

Parallelism

Each xᵢ^(k+1) depends only on x^(k) — all can be computed independently. Ideal for GPU/distributed computing. Gauss-Seidel is sequential but usually converges faster.

Convergence

Sufficient: strict diagonal dominance |aᵢᵢ| > Σⱼ≠ᵢ|aᵢⱼ|. Necessary and sufficient: spectral radius ρ(D⁻¹(L+U)) < 1.

Step-by-Step Instructions

  1. 1Select a system.
  2. 2Set tolerance.
  3. 3View iterations.
  4. 4Check convergence.
  5. 5Get solution.

Jacobi Iteration Solver — Frequently Asked Questions

Why use Jacobi over direct methods?+

For very large sparse systems (millions of unknowns), direct methods need too much memory. Jacobi only needs the non-zero entries and two vectors. It's also embarrassingly parallel.

What is diagonal dominance?+

A matrix is diagonally dominant if |aᵢᵢ| > Σⱼ≠ᵢ|aᵢⱼ| for all rows. This guarantees convergence of both Jacobi and Gauss-Seidel. Many physical systems naturally produce diagonally dominant matrices.

How does Jacobi compare to Gauss-Seidel?+

Jacobi: all updates use old values (parallelizable). Gauss-Seidel: uses newest values (sequential, ~2× faster convergence). For parallel hardware, Jacobi wins; for serial, Gauss-Seidel wins.

Share this tool: