物理学
# 物理学
# ベクトル解析
# 電磁気学
# 解析力学
波動方程式の離散化
$$ \begin{aligned} \frac{\partial^2u}{\partial t^2} &= v^2\left(\frac{\partial^2u}{\partial x^2} + \frac{\partial^2u}{\partial y^2}\right) \\ \frac{u_{i,j}^{n+1}-2u_{i,j}^n+u_{i,j}^{n-1}}{\Delta t^2} &= v^2\left(\frac{u_{i,j}^{n+1}-2u_{i,j}^n+u_{i,j}^{n-1}}{\Delta x^2} + \frac{u_{i,j}^{n+1}-2u_{i,j}^n+u_{i,j}^{n-1}}{\Delta y^2}\right) \\ u_{i,j}^{n+1} &= 2u_{i,j}^n - u_{i,j}^{n-1} + \Delta t^2v^2\left(\frac{u_{i,j}^{n+1}-2u_{i,j}^n+u_{i,j}^{n-1}}{\Delta x^2} + \frac{u_{i,j}^{n+1}-2u_{i,j}^n+u_{i,j}^{n-1}}{\Delta y^2}\right) \end{aligned} $$