Ordinary Differential Equations

Diffeq not that useful for Computer Science, most problems in CS are perhaps discrete versions of diffeq, gradient descent as an example.

Another example is the fast Fourier transform (FFT) algorithm which is based on the integral formulation of diffeq.

Many discrete filters act as approximation to analog filters. It is possible to derive diffeq to analyze their performance in the continuous domain.

Partial Differential Equations