Numerical Methods & Scientific Computing

1-D Poisson Equation Solver

Solve a one-dimensional Poisson boundary-value problem on 0≤x≤1. Select a source function, choose grid density and solve the second-order finite-difference tridiagonal system directly.

Finite-difference PDE workbench

1-D Poisson Equation

Domain is normalized to 0 ≤ x ≤ 1 unless the 2-D Laplace solver is selected.

How this tool works

At each interior point, −u″≈(2uᵢ−uᵢ₋₁−uᵢ₊₁)/Δx²=fᵢ. With fixed endpoint values, the interior equations form a symmetric tridiagonal linear system.

Example

Choose f(x)=π²sin(πx). With zero endpoints, the exact solution is sin(πx), making it a convenient grid-convergence check.

Common questions

What boundary conditions are used?

This calculator uses homogeneous Dirichlet conditions u(0)=u(1)=0.

What is the expected spatial order?

The centered second derivative is second-order accurate in Δx for smooth solutions.