这是代码:
\documentclass{article}
\usepackage{calrsfs}
\usepackage{amsmath,array}
\usepackage[english]{babel}
\usepackage{amsfonts}
% Useful packages
\usepackage{amsmath}
\usepackage{graphicx}
\DeclareMathOperator{\Nat}{Nat}
\DeclareMathOperator{\Hom}{Hom}
\begin{document}
\[
\renewcommand{\arraystretch}{1.2}’’
\setlength{\arraycolsep}{0pt}
\begin{array}{l@{\;}c>{{}}c<{{}}l}
\Phi\colon & (l^\infty(\mathbb{N},\mathbb{C}),\| \cdot \|_{l^\infty} & \longrightarrow & ((l^1(\mathbb{N},\mathbb{C}),\| \cdot \|_{l^1}) \\
& u_n = (u_n)_{n\in \mathbb{N}} & \longmapsto &
\begin{array}[t]{|@{\;}l@{\;}l}
\Phi\colon & (l^1(\mathbb{N},\mathbb{C}) \longrightarrow \mathbb{C} \\
& x = (x_n)_{n \in \mathbb{N}} \longmapsto \sum\limits_{n=0}^\infty u_n x_n
\end{array}
\end{array}
\]
\end{document}
尽管如此,正如你所注意到的黄色的在我的版本中缺少,但我找不到原因。
此外,这些行\begin{array}{l@{\;}c>{{}}c<{{}}l}
和\begin{array}[t]{|@{\;}l@{\;}l}
命令\column
不是我写的,老实说,我真的不明白这些长参数begin{array}
和\column
的作用。所以如果有人能启发我,那就太好了。
最后,如果有人能演示如何制作有和没有括号由于我很困惑,我将非常感激。
预先感谢您的帮助 !
答案1
我将把每列从 4 列改为 3 列array
。
我使用了\rightarrow
and\mapsto
代替\longrightarrow
and \longmapsto
,以便更好地接近您发布的屏幕截图。显然,如果您愿意,您可以完全自由地使用\longrightarrow
and 。\longmapsto
\documentclass{article}
\usepackage{mathtools} % for \DeclarePairedDelimiter macro
%%\usepackage{amsmath} % mathtools loads amsmath automatically
\usepackage{array} % for \newcolumntype macro
\newcolumntype{C}{>{{}}c<{{}}} % col. type for binary and relational operators
\usepackage[english]{babel}
\usepackage{amssymb} % amssymb loads amsfonts automatically
% \usepackage{calrsfs} % not needed for this example
%%\usepackage{amsmath} % don't load packages twice
%\usepackage{graphicx} % not needed for this example
%\DeclareMathOperator{\Nat}{Nat} % not needed for this example
%\DeclareMathOperator{\Hom}{Hom} % not needed for this example
\DeclarePairedDelimiter{\norm}{\lVert}{\rVert}
\newcommand\blanknorm{\norm{{}\cdot{}}} % 'generic norm'
\begin{document}
\[
\setlength{\arraycolsep}{0pt} % default: 5pt
\begin{array}{rCl}
\Phi\colon\
(l^{\infty}(\mathbb{N},\mathbb{C}), \blanknorm_{l^{\infty}}) &
\rightarrow &
\bigl( % I would enlarge the 'outer' pair of parentheses
{( l^1(\mathbb{N}, \mathbb{C}), \blanknorm_{l^1} )}',
\blanknorm_{(l^1)'}
\bigr ) \\[2\jot] % end of row 1: add a bit of vertical whitespace
u_n = (u_n)_{n\in\mathbb{N}} &
\mapsto &
\left\{
\begin{array}{rCl}
\Phi(u)\colon\qquad l^1(\mathbb{N},\mathbb{C}) &
\rightarrow &
\mathbb{C} \\[\jot]
x = (x_n)_{n \in \mathbb{N}} &
\mapsto &
\sum_{n=0}^{+\infty} u_n x_n
\end{array}
\right.
\end{array}
\]
\end{document}