好表

ltxtest.tex

\documentclass{article}
\usepackage{booktabs}
\begin{document}
\begin{table}
  \centering
  \caption{Maximum norm errors for different step sizes.}
\[
  \begin{array}{cccc}
  \toprule
  h & \tau & E_{\infty}(h,\tau) &log_2\frac{E_{\infty}(2h,4\tau)}{E_{\infty}(h,\tau)}\\
  \midrule
  1/10 & 1/100 & 6.128e-05 & *\\
  1/20 & 1/400 & 3.821e-06 & 4.003\\
  1/40 & 1/1600 & 2.390e-07 & 3.999\\
  1/80 & 1/3200 & 1.493e-08 & 4.001\\
  \bottomrule
  \end{array}
\]
\end{table}
\end{document}