## 2018年4月13日 星期五

### Convolution 的意義

Convolution 的意義
The convolution of f and g is written fg, using an asterisk or star. It is defined as the integral of the product of the two functions after one is reversed and shifted. As such, it is a particular kind of integral transform:
{\displaystyle {\begin{aligned}(f*g)(t)&\,{\stackrel {\mathrm {def} }{=}}\ \int _{-\infty }^{\infty }f(\tau )g(t-\tau )\,d\tau \\&=\int _{-\infty }^{\infty }f(t-\tau )g(\tau )\,d\tau .\end{aligned}}}