Stiff equations

Stiff equations are a type of differential equation where solutions change rapidly over a small interval, alongside other parts that change slowly. This causes numerical methods to struggle: simple techniques require very small steps to remain stable, making computations inefficient. They commonly appear in systems with processes happening at different speeds, such as chemical reactions or electrical circuits. To solve them efficiently, specialized methods that handle these fast and slow changes simultaneously are used, allowing accurate solutions without excessive computation time.