有用的命令

$ \newcommand{\infint}{{\int_{-\infty}^{\infty}}} \newcommand{\ie}{\textit{i.e.}\ } \newcommand{\eg}{\textit{e.g.}\ } \newcommand{\pfrac}[2]{{\frac{\partial #1}{\partial #2}}} \newcommand{\eqn}[1]{Eq.\ (\ref{#1})} $
Putty command line:
start d:\softwares\putty.exe -ssh -pw xxx -P 1234 user@localhost

Run VirtualBox headless:
VBoxHeadless.exe -s Sage-5.0

Sage interactive:

Latex newcommad command:

$$\infint f(x)dx$$ $$\pfrac{L}{q_n},\quad \pfrac{}{x_i}$$