~% -*- coding: utf-8 -*- ~% This is part of the book TeX for the Impatient. ~% Copyright (C) 2003 Paul W. Abrahams, Kathryn A. Hargreaves, Karl Berry. ~% See file fdl.tex for copying conditions. ~% TeX ignores anything on a line after a % ~% The next two lines define fonts for the title % TeX 忽略一行中 % 之后的任何内容 % 下面两行定义标题所用的字体 \font\xmplbx = cmbx10 scaled \magstephalf \font\xmplbxti = cmbxti10 scaled \magstephalf ~% Now here's the title. % 现在是标题行 ~%\leftline{\xmplbx Example !xmpnum:\quad\xmplbxti Entering simple text} ~\bookmark{2}{例!xmpnum：输入简单文本}% \leftline{\xmplbx 例!xmpnum:\quad\xmplbxti 输入简单文本} \vglue .5\baselineskip % skip an extra half line ~\count255 = \pageno ~\xdef\examplepage{\number\count255} ~\markinfo{Example 1: Entering simple text} ~\ifrewritetocfile ~\write\tocfile{\string\tocsectionentry{输入简单文本}{\examplepage}}% ~\fi ~^^{脚注} ^^{注释} ^^{标点} ^^{引号} ~^^{空格符} ^^{横线号} ^^{段落//结束段落} ~\edef\examplepageno{\number\count255}% ~%It's easy to prepare ordinary text for \TeX\ since ~%\TeX\ usually doesn't care about how you break up your input into ~%lines. It treats the end of a line of text like a space.% ~%\footnote \dag{\TeX\ treats a tab like a space too, as we point ~%out in this {\it footnote}.} If you don't want a space there, ~%put a per% ~%cent sign (the comment character) at the end of the line. ~% \TeX\ ignores spaces at the start of a line, and treats more ~%than one space as equivalent to a single space, ~%even after a period. You indicate a new paragraph by ~%skipping a line (or more than one line). 由于 \TeX\ 并不关心原始的输入文本中的换行，因此，我们无须关心 应该给其提供何种格式化的文本。在 \TeX\ 看来，输入文本中的换行符 和空格等价。% \footnote \dag{\TeX\ 将 Tab 也当作空格处理, 就如你在这个 {\it 脚注}所见到的一样。} 如果你不想在行尾处看到空格， 可以在行尾处写一个百分号（注释符号）。\TeX\ 忽略行首的空格， 对多于一个的空格当做一个单独的空格看待 --- 哪怕这些空格位于 句号后面。你可以用一个或者多个空白行表示一个新的段落的开始。 ~%When \TeX\ sees a period followed by a space (or the end of the ~%line, which is equivalent), it ordinarily assumes you've ended a ~%sentence and inserts a little extra space after the period. It ~%treats question marks and exclamation points the same way. 当 \TeX\ 看见一个句号后面紧接着一个空格（或者是一个行结束符，这 两者等价）时，它通常会认为此句号代表一句话的结束，并在句号的后面 加上一点小小的空格。同样的处理还适用于问号和惊叹号。 ~% But \TeX's rules for handling periods sometimes need fine ~%tuning. \TeX\ assumes that a capital letter before a period ~%doesn't end the sentence, so you have to do something a little ~%different if, say, you're writing about DNA\null. 有时需要微调 \TeX\ 处理句号的方式。当句号前面紧跟着标题字 母（大写字母）时，\TeX\ 会认为这个句号并不做为句子的结束符， 因此在这种情况下，你需要作一些小改动。例如：我们这样写 DNA\null. ~% The \null prevents TeX from perceiving the capital `A' ~% as being next to the period. % \null 可以阻止 \TeX\ 感知句号前面的标题字母 `A'。 ~%It's a good idea to tie words together in references such as ~%``see Fig.~8'' and in names such as V.~I\null. Lenin and in ~%$\ldots$ so that \TeX\ will never split them in an awkward place ~%between two lines. (The three dots indicate an ellipsis.) ~% 这个 references 不知道这样翻译对不对 如果想将多个单词绑定到一起，中间不分行，则可以将它们放入一个引用中， 例如：``见 Fig.~8''；或者名字中，例如：V.~I\null. Lenin； 或者省略号 $\ldots$。在这样的情况下，\TeX\ 不会在它们之间断行 （三个点表示省略号）。 ~%You should put quotations in pairs of left and right ~%single ``quotes'' so that you get the correct left and right ~%double quotation marks. ``For adjacent single and double ~%quotation marks, insert a `thinspace'\thinspace''. You can ~%get en-dashes--like so, and em-dashes---like so. 为得到正确的左右双引号，你需要用两个左右单``引号''。 ``在相邻的单引号和双引号之间，要插入一个`小间隔'\thinspace''。 连接号--可以这样写，而破折号---可以这样写。 ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Indentation}% !xmpheaddef \xmpheader !xmpnum/{缩进}% !xmpheaddef ~^^{缩进} ^^{边距} ^^{段落//窄段落} ~%\noindent Now let's see how to control indentation. If an ~%ordinary word processor can do it, so surely can \TeX. Note ~%that this paragraph isn't indented. \noindent 现在让我们来看看如何控制缩进。如果一个普通的文字处理 程序都能处理缩进的话，那 \TeX\ 一定也能。请注意，本段并未缩进。 ~%Usually you'll either want to indent paragraphs or to leave ~%extra space between them. Since we haven't changed anything ~%yet, this paragraph is indented. 通常来说，你会想在段落的起始处安排缩进，在段落之间安排一些额外 的空白。由于我们在此尚未做任何特殊处理，因此本段是缩进的。 {\parindent = 0pt \parskip = 6pt ~% The left brace starts a group containing the unindented text. % 这里的左括弧包裹了一组不缩进的文本 ~%Let's do these two paragraphs a different way, ~%with no indentation and six printer's points of extra space ~%between paragraphs. 让我们对这两个段落作一些特殊处理，这两段将不缩进，并且两段 之间有 6pt 宽的空白。 ~%So here's another paragraph that we're typesetting without ~%indentation. If we didn't put space between these paragraphs, ~%you would have a hard time knowing where one ends ~%and the next begins. 这是第二段不缩进的文字。如果不在这两段之间插入空白的话，将很难 分辨段与段之间的结束和起始。 \par % The paragraph *must* be ended within the group. }% The right brace ends the group containing unindented text. ~%It's also possible to indent both sides of entire paragraphs. ~%The next three paragraphs illustrate this: 你也能在段落的两边同时缩进，下面的 3 段文字演示了双边缩进的效果： \smallskip % Provide a little extra space here. % Skips like this and \vskip below end a paragraph. {\narrower ~% ``We've indented this paragraph on both sides by the paragraph ~% indentation. This is often a good way to set long quotations.'' ``我们对这一段作了双边缩进的处理。在长段引用时，通常都会这么做。'' ~%``You can do multiple paragraphs this way if you choose. This ~%is the second paragraph that's singly indented.''\par} ``如果你愿意的话，可以同时对多个段落作如此处理. 这是 第二个轻微缩进的段落.''\par} ~%{\narrower \narrower You can even make paragraphs doubly narrow ~%if that's what you need. This is an example of a doubly ~%narrowed paragraph.\par} {\narrower \narrower 如果需要，你也可以让段落缩进双倍长度。 这就是一个双倍缩进段落的例子.\par} \vskip 1pc % Skip down one pica for visual separation. ~%In this paragraph we're back to the normal margins, as you can ~%see for yourself. We'll let it run on a little longer so that ~%the margins are clearly visible. 在这一段，如你所见，我们返回到正常的边距状态。我们尽量让这一段 稍微长一点，这样你可以更清楚地看到边距的效果。 ~%{\leftskip .5in Now we'll indent the left margin by half ~%an inch and leave the right margin at its usual position.\par} {\leftskip .5in 现在这一段，我们将其调整为左边距为半英尺，而 右边距保持原样。\par} ~%{\rightskip .5in Finally, we'll indent the right margin by half ~%an inch and leave the left margin at its usual position.\par} {\rightskip .5in 最后，我们将本段调整为右边距半英尺，而左边距保持 原样。\par} ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Fonts and special characters}% !xmpheaddef \xmpheader !xmpnum/{字体和特殊字符}% !xmpheaddef \chardef \\ = `\\ % Let \\ denote a backslash. ~^^{字体} ^^{字符//特殊字符} ^^{重音} ~^^{音符} ^^{花色} ~\ifoldeplain ~^^|$| ^^|&| ^^|#| ^^|_| ^^|%| ^^|^| ^^|~| ^^|{| ^^|}| \indexchar \ ~\fi ~%{\it Here are a few words in an italic font}, {\bf a ~%few words in a boldface font}, {\it and a\/ {\bf mixture} ~%of the two, with two\/ {\rm roman words} inserted}. ~%Where an italic font is followed by a nonitalic font, we've ~%inserted an ``italic correction'' ({\tt \\/}) to make the ~%spacing look right. {\it 这是一些斜体字词}, {\bf 一些粗体字词}， {\it 以及一些 {\bf 二者混合的效果}， 我们在中间插入一些 {\rm 正常的字词} }. 当斜体字后面紧跟非斜体字时, 我们在其间插入一个``倾斜校正'' ({\tt \\/})，使得中间的空白看起来较舒适。 ~%Here's a {\sevenrm smaller} word---but the standard \TeX\ ~%fonts won't give you anything smaller than {\fiverm this}. 这是一些{\sevenrm 更小的} 字词---可是标准的 \TeX\ 字体并不会给出小于 {\fiverm 如此大小}的字体。 ~%If you need any of the ten characters: 如果你需要以下十个字符任意之一： \medskip \centerline{\$ \quad \& \quad \# \quad \_ \quad \% \quad \char `\^ \quad \char `\~ \quad $\{$ \quad $\}$ \quad $\backslash$} % The \quad inserts an em space between characters. \medskip ~%\noindent you'll need to write them a special way. Look at ~%the facing page to see how to do it. \noindent 你需要通过特殊的方式来写他们。参照对开页， 学习正确的记录这些特殊字符的方法. ~%\TeX\ has the accents and letters that you'll need ~%for French words such as {\it r\^ ole\/} and {\it \' ~%el\` eve\/}, for German words such as {\it Schu\ss\/}, ~%and for words in several other languages as well. ~%You'll find a complete list of \TeX's accents and letters ~%of European languages on !xrefdelim[accents] and !xrefdelim[fornlets]. \TeX\ 拥有一些语音和字母，可以用于某些法语词， 例如：{\it r\^ ole\/} 以及{\it \'el\` eve\/}， 或者德语词，例如 {\it Schu\ss\/}，或者某些别的什么语言。 你可以在 !xrefdelim[accents] 和 !xrefdelim[fornlets] 处 找到 \TeX\ 的 欧洲语音和字母表。 ~%You can also get Greek letters such as ``$\alpha$'' and ~%``$\Omega$'' for use in math, card suits such as ~%``$\spadesuit$'' and ``$\diamondsuit$'', music symbols ~%such as ``$\sharp$'' and ``$\flat$'', and many other special ~%symbols that you'll find listed on !xrefdelim[specsyms]. ~%\TeX\ will only accept these sorts of special symbols in its ~%``math mode'', so you'll need to enclose them ~%within `{\tt \$}' characters. 你也可以写一些希腊字母，例如数学中的 ``$\alpha$'' 以及 ``$\Omega$'' , 扑克牌中的 ``$\spadesuit$'' 以及 ``$\diamondsuit$'', 一些音乐符号，例如： ``$\sharp$'' 和 ``$\flat$'', 以及一些你可以在 !xrefdelim[specsyms] 找到的各种符号。\TeX\ 仅在 ``数学模式'' 下接受这些符号, 因此， 你需要将它们放在两个 `{\tt \$}' 字符中间。 ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Interline spacing}% !xmpheaddef \xmpheader !xmpnum/{行间距}% !xmpheaddef ~^^{间隔//行间距} ^^{基线} \baselineskip = 2\baselineskip % double spacing \parskip = \baselineskip % Skip a line between paragraphs. \parindent = 3em % Increase indentation of paragraphs. % The following macro definition gives us nice inline % fractions. You'll find it in our eplain macros. \def\frac#1/#2{\leavevmode \kern.1em \raise .5ex \hbox{\the\scriptfont0 #1}% \kern-.1em $/$% \kern-.15em \lower .25ex \hbox{\the\scriptfont0 #2}% }% ~%Once in a while you may want to print a document with extra ~%space between the lines. For instance, bills before Congress ~%are printed this way so that the legislators can mark them up. ~%For the same reason, book publishers usually insist that ~%manuscripts be double-spaced. Double spacing is rarely ~%appropriate for finished documents, however. 有的时候，你会想在文档的文字行之间增加一些空白。例如：议会的 某些讨论稿需要这样做，使得议院们能够在其上作一些标记。书商们 也基于同样的理由，要求作者提交的手稿具有双倍的行间距。当然， 对最终的出版物来说，双倍行间距的情形极其少见。 ~%A baseline is an imaginary line that acts like the lines ~%on a pad of ruled paper. You can control the interline ~%spacing---what printers call ``leading''---% ~%by setting the amount of space between baselines. Take a ~%look at the input to see how to do it. You could use ~%the same method for $1\;1/2$ spacing as well, using {\tt 1.5} ~%instead of {\tt 2}. (You can also write $1\frac 1/2$ ~%a nicer way.) 基线是一条想象出来的线，其作用类似于带横格标记的纸张上 横格线的作用。你可以通过控制基线间的距离来控制两行文字 之间的距离 --- 打印机管这个距离叫做 ``起始空白''。具体 的做法可以参看这段的源文件。你可以用{\tt 1.5}取代{\tt 2} 获得 $1\;1/2$空白的效果。（或者可以写成更好看的 $1\frac 1/2$ 形式。） % Here we've used the macro definition given above. ~%For this example we've also increased the paragraph indentation ~%and skipped an extra line between paragraphs. 做为举例，我们这里增加了段落的缩进，并且在两段之间增加了一个空行。 ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Spacing, rules, and boxes}% !xmpheaddef \xmpheader !xmpnum/{间隔、标线和盒子}% !xmpheaddef ~^^{描述列表} ^^{盒子//绘制盒子} ^^{修订线} ~%Here's an example of a ``description list''. In practice you'd ~%be better off using a macro to avoid the repetitive constructs ~%and to make sure that the subhead widths are wide enough: 这里展示的是 ``描述列表''的实例。实际使用时，最好将这些重复结构 定义成宏，并且保证子标题的宽度足够宽。 \bigskip ~% Call the indentation for descriptions \descindent ~% and set it to 8 picas. % 用 \descindent 表示描述列表的缩进量，并设定它的值为 8 派卡。 \newdimen\descindent \descindent = 8pc ~% Indent paragraphs by \descindent. ~% Skip an additional half line between paragraphs. % 整个段落缩进 \descindent。段落间增加半个行距的间距。 {\noindent \leftskip = \descindent \parskip = .5\baselineskip ~% Move the description to the left of the paragraph. % 将描述放在段落的左边。 \llap{\hbox to \descindent{\bf Queen of Hearts\hfil}}% An ill-tempered woman, prone to saying ``Off with his head!!''\ at the slightest provocation.\par \noindent\llap{\hbox to \descindent{\bf Cheshire Cat\hfil}}% A cat with an enormous smile that Alice found in a tree.\par \noindent\llap{\hbox to \descindent{\bf Mock Turtle\hfil}}% A lachrymose creature, quite a storyteller, who was a companion to the Gryphon. Reputedly the prin\-cipal ingredient of Mock Turtle Soup. \par} \bigskip\hrule\bigskip % A line with vertical space around it. ~%Here's an example of some words in a ruled box, just as ~%Lewis Carroll wrote them: 这个例子在一个标线盒子中放入一些词句，它们是路易斯·卡罗所写的： \bigskip ~% Put 8pt of space between the text and the surrounding rules. % 在文本和四周标线之间留有 8pt 宽的间隔。 \hbox{\vrule\vbox{\hrule \hbox spread 8pt{\hfil\vbox spread 8pt{\vfil ~% \hbox{Who would not give all else for twop}% ~% \hbox{ennyworth only of Beautiful Soup?}% \hbox{谁不是最想尝一尝，}% \hbox{两便士一碗的好汤？}% \vfil}\hfil} \hrule}\vrule}% \bigskip\line{\hfil\hbox to 3in{\leaders\hbox{ * }\hfil}\hfil} \bigskip \line{\hskip -4pt\vrule\hfil\vbox{ ~%Here we've gotten the effect of a revision bar on the material ~%in this paragraph. The revision bar might indicate a change.}} 我们给此段落内容添加了修订线效果。修订线用于表示内容改动。}} ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Odds and ends}% !xmpheaddef \xmpheader !xmpnum/{杂项}% !xmpheaddef ~^^{连字} ^^{定理} ^^{引理} ^^{有序列表} ~^^{居左对齐} ^^{居右对齐} ^^{居中对齐} ~%\chardef \\ = `\\ % Let \\ denote a backslash. \chardef \\ = `\\ % 用 \\ 表示反斜杠。 \footline{\hfil{\tenit - \folio -}\hfil} ~\global\footline{\hfil{\tenit - \folio\ -}\hfil} ~% \footline provides a footer line. ~% Here it's a centered, italicized page number. % \footline 给出页脚行；此处为居中的意大利体页码。 ~%\TeX\ knows how to hyphenate words, but it isn't infallible. ~%If you are discussing the chemical ~%${\it 5}$-[p-(Flouro\-sul\-fonyl)ben\-zoyl]-l,% ~%$N^6$-ethe\-no\-adeno\-sine ~%and \TeX\ complains to you about an ``overfull hbox'', try ~%inserting some ``discretionary hyphens''. The notation ~%`{\tt \\-}' tells \TeX\ about a dis\-cre\-tion\-ary hyphen, ~%that is, one that it might not have inserted otherwise. \TeX\ 懂得如何将单词连字化，但它并非绝对可靠的。若你在讨论化学 ${\it 5}$-[p-(Flouro\-sul\-fonyl)ben\-zoyl]-l,% $N^6$-ethe\-no\-adeno\-sine 时， \TeX\ 给出关于``水平盒子溢出''的警告， 你可以尝试插入某些``自定连字符''。 `{\tt \\-}'记号告诉 \TeX\ 一个自定连字符位置； 在此位置 \TeX\ 本来是不会插入连字符的。 \medskip ~%{\raggedright You can typeset text unjustified, i.e., with ~%an uneven right margin. In the old days, before word ~%processors were common, typewritten documents were ~%unjustified because there was no convenient alternative. ~%Some people prefer text to be unjustified so that the ~%spacing between words can be uniform. Most books are set ~%with justified margins, but not all. \par} {\raggedright 你可以不对齐地排版文字，即让右页边不对齐。 在过去，文字处理软件还未普及， 因为没有其他方便的选择，排版的文档都是不对齐的。 有些人更喜欢不对齐地排版文字，因为此时单词间距是一致的。 大部分书籍都设置为页边对齐，但并非都是。\par} ~%\proclaim Assertion 27. There is an easy way to typeset ~%the headings of assertions, lemmas, theorems, etc. \proclaim 断言 27. 有很简单的方法排版断言、引理、定理等的标题。 ~%Here's an example of how to typeset an itemized list two ~%levels deep. If you need more levels, you'll have to ~%program it yourself, alas. ~%\smallskip ~%\item {1.} This is the first item. ~%\item {2.} This is the second item. It consists of two ~%paragraphs. We've indented the second paragraph so that ~%you can easily see where it starts. 这个例子显示如何排版两层的有序列表。 如果需要更多层级，唉，你得自己编程。 \smallskip \item {1.} 这是第一个列表项。 \item {2.} 这是第二个列表项。它由两个段落组成。 为让你看清楚第二个段落从哪里开始，我们缩进了该段落。 ~%\item{} \indent The second paragraph has three subitems ~%underneath it. ~%\itemitem {(a)} This is the first subitem. ~%\itemitem {(b)} This is the second subitem. ~%\itemitem {(c)} This is the third subitem. ~%\item {$\bullet$} This is a strange-looking item because it's ~%completely different from the others. \item{} \indent 第二个段落下边有三个子列表项。 \itemitem {(a)} 这是第一个子列表项。 \itemitem {(b)} 这是第二个子列表项。 \itemitem {(c)} 这是第三个子列表项。 \item {$\bullet$} 这是一个看起来很奇怪的列表项， 因为它和其他列表项不同。 \smallskip ~%\leftline{Here's a left-justified line.$\Leftarrow$} ~%\rightline{$\Rightarrow$Here's a right-justified line.} ~%\centerline{$\Rightarrow$Here's a centered line.$\Leftarrow$} \leftline{这是一个左对齐的行。$\Leftarrow$} \rightline{$\Rightarrow$这是一个右对齐的行。} \centerline{$\Rightarrow$这是一个居中的行。$\Leftarrow$} ~% Don't try to use these commands within a paragraph. % 不要在段落内部使用这些命令。 ~%\bye % end the document \bye % 结束此文档 ::: ~%\xmpheader !xmpnum/{Using fonts from other sources}% !xmpheaddef \xmpheader !xmpnum/{使用其他来源的字体}% !xmpheaddef ~\xrdef{palatino} ~\idxref{Palatino 字体} ~\idxref{Zapf, Hermann} ~\idxref{计算机现代字体} ^^{\Metafont} \font\tenrm = pplr % Palatino % Define a macro for invoking Palatino. \def\pal{\let\rm = \tenrm \baselineskip=12.5pt \rm} \pal % Use Palatino from now on. ~%You aren't restricted to using the Computer Modern fonts that ~%come with \TeX. Other fonts are available from many sources, ~%and you may prefer them. For instance, we've set this page ~%in 10-point Palatino Roman. Palatino was designed by ~%Hermann Zapf, considered to be one of the greatest type ~%designers of the twentieth century. This page will ~%give you some idea of what it looks like. 你并不局限于只能使用随 \TeX 发行的 Computer Modern 系列字体。 从其他很多渠道你都可以得到一些你可能会更喜欢的字体。例如我们 当前页面就被设置为 10p 大小的 Palatino Roman 字体。Palatino 是一种由 Hermann Zapf 所设计的字体，它被认为是二十世纪最伟大的 字体设计之一。从本页的输出可以获得关于这个字体的一些直观印 象（由于译本的缘故，本页的字体并未被设为 Palatino 字体）。 ~%Fonts can be provided either as outlines or as bitmaps. An ~%outline font describes the shapes of the characters, while a ~%bitmap font specifies each pixel (dot) that makes up each ~%character. A font outline can be used to generate many ~%different sizes of the same font. The Metafont program ~%that's associated with \TeX\ provides a particularly ~%powerful way of generating bitmap fonts, but it's not the ~%only way. 字体既可以是轮廓字体，也可以是位图字体。轮廓字体的意思是它 描述的是各个字符的形状，而位图字体则是标识了每个字符形状所 占据的像素点。轮廓字体可用来产生同一种字体的多种不同大小。 随 \TeX\ 而发行的 metafont 程序是一个产生位图字体的强大工具， 而且它并不是唯一的工具。 ~%The fact that a single outline can generate a great range of ~%point sizes for a font tempts many vendors of digital ~%typefaces to provide just one set of outlines for a typeface ~%such as Palatino Roman. This may be a sensible economic ~%decision, but it is an aesthetic sacrifice. Fonts cannot be ~%scaled up and down linearly without loss of quality. ~%Larger sizes of letters should not, in general, have the ~%same proportions as smaller sizes; they just don't look ~%right. For example, a font that's linearly scaled down will ~%tend to have too little space between strokes, and its ~%x-height will be too~small. % tie added to avoid widow word 由于单一的轮廓字体文件既可生成多种不同大小的字体，因此很多 数字字体提供商倾向于仅提供字体的单一文件 ——例如 Palatino Roman 即是如此。这也许是个经济的决定，可它却同时是个美学上 的重大牺牲。字体无法做到在不损害其显示质量的前提下，线性地 放大或者缩小。一个字符的大字体版本，通常来说，与小字体的版 本应该有不同的比例 —— 而如果我们坚持这么做的话，其结果看 起来将不会那么好看。例如：如果将一个字体线性缩小的话，其各 笔画间的间距将会显得过窄，而它的 x-height 值也会显得过小。 ~%A type designer can compensate for these changes by ~%providing different outlines for different point sizes, but ~%it's necessary to go to the expense of designing these ~%different outlines. One of the great advantages of Metafont ~%is that it's possible to parameterize the descriptions of ~%characters in a font. Metafont can then maintain the ~%typographical quality of characters over a range of point ~%sizes by adjusting the character shapes accordingly. 字体的设计者可以为不同大小的字体设计不同的轮廓形状，从而 对这个问题进行弥补，可这同时需要付出额外的代价。使用 Metafont 程序的一个巨大的好处就是可以将字符符号形状的描述参数化。 这样在改变字体大小的时候，Metafont 可以视情况做一些自动处理， 从而得到较好的效果。 ~%\bye % end the document \bye % 结束此文档 ::: ~\idxref{蘑菇} ~%\xmpheader !xmpnum/{A ruled table}% !xmpheaddef \xmpheader !xmpnum/{标线表格}% !xmpheaddef \bigskip ~%\offinterlineskip % So the vertical rules are connected. \offinterlineskip % 让竖直标线连接起来 ~% \tablerule constructs a thin rule across the table. % \tablerule 构造横穿表格的细标线 \def\tablerule{\noalign{\hrule}} ~% \tableskip creates 9pt of space between entries. % \tableskip 在单元格之间生成 9pt 的空隙 \def\tableskip{\omit&height 9pt&&&\omit\cr} ~% & separates templates for each column. TeX substitutes ~% the text of the entries for #. We must have a strut ~% present in every row of the table; otherwise, the boxes ~% won't butt together properly, and the rules won't join. % 用 & 分开模版各列。TeX 将把 # 替换为单元格的文本。 % 在表格每行都要有一个支架（strut）； % 否则盒子将不能良好接合，标线也不能连接起来。 ~%\halign{\tabskip = .7em plus 1em % glue between columns ~% Use \vtop for short multiline entries in the first column. ~% Typeset the lines ragged right, without hyphenation. ~% \vtop{\hsize=6pc\pretolerance = 10000\hbadness = 10000 ~% \normalbaselines\noindent\it#\strut}% ~% &\vrule #&#\hfil &\vrule #% the rules and middle column \halign{\tabskip = .7em plus 1em % 各列之间的粘连 % 用 \vtop 得到表格第一列中的多行单元格。 % 让多行文本右边不对齐，且不连字化。 \vtop{\hsize=6pc\pretolerance = 10000\hbadness = 10000 \normalbaselines\noindent\it#\strut}% &\vrule #&#\hfil &\vrule #% 标线和中间各列 ~%% Use \vtop to get whole paragraphs in the last column. ~% &\vtop{\hsize=11pc \parindent=0pt \normalbaselineskip=12pt ~% \normalbaselines \rightskip=3pt plus2em #}\cr % 用 \vtop 得到表格最后一列中的段落。 &\vtop{\hsize=11pc \parindent=0pt \normalbaselineskip=12pt \normalbaselines \rightskip=3pt plus2em #}\cr ~% The table rows begin here. % 表格各行从这里开始。 ~%\noalign{\hrule height2pt depth2pt \vskip3pt} ~% % The header row spans all the columns. ~% \multispan5\bf Some Choice Edible Mushrooms\hfil\strut\cr \noalign{\hrule height2pt depth2pt \vskip3pt} % 表头行横跨各列。 \multispan5\bf 一些上等的食用蘑菇\hfil\strut\cr ~%\noalign{\vskip3pt} \tablerule ~% \omit&height 3pt&\omit&&\omit\cr ~% \bf Botanical&&\bf Common&&\omit \bf Identifying \hfil\cr ~%\noalign{\vskip -2pt}% close up lines of heading ~% \bf Name&&\bf Name &&\omit \bf Characteristics \hfil\cr \noalign{\vskip3pt} \tablerule \omit&height 3pt&\omit&&\omit\cr \bf 学名&&\bf 常用名&&\omit \bf 识别特征 \hfil\cr ~%\tableskip Pleurotus ostreatus&&Oyster mushroom&& ~% Grows in shelf\kern 1pt like clusters on stumps or logs, ~% % without the kern, the `f' and `l' would be too close ~% pink-gray oyster-shaped caps, stem short or absent.\cr \tableskip Pleurotus ostreatus&&平菇&& Grows in shelf\kern 1pt like clusters on stumps or logs, % 若不加上 \kern ，`f' 和 `l' 将挨得太近 pink-gray oyster-shaped caps, stem short or absent.\cr ~%\tableskip Lactarius hygrophoroides&&Milky hygroph&& ~% Butterscotch-brown cap and stem, copious white latex, ~% often on ground in woods near streams.\cr \tableskip Lactarius hygrophoroides&&稀褶乳菇&& Butterscotch-brown cap and stem, copious white latex, often on ground in woods near streams.\cr ~%\tableskip Morchella esculenta&&White morel&&Conical cap ~% with black pits and white ridges; no gills. Often found ~% near old apple trees and dying elms in the spring.\cr \tableskip Morchella esculenta&&羊肚菌&&Conical cap with black pits and white ridges; no gills. Often found near old apple trees and dying elms in the spring.\cr ~%\tableskip Boletus edulus&&King bolete&&Reddish-brown to ~% tan cap with yellow pores (white when young), ~% bulbous stem, often near conifers, birch, or~aspen.\cr \tableskip Boletus edulus&&美味牛肝菌&&Reddish-brown to tan cap with yellow pores (white when young), bulbous stem, often near conifers, birch, or~aspen.\cr \tableskip \tablerule \noalign{\vskip 2pt} \tablerule }\bye ::: ~%\xmpheader !xmpnum/{Typesetting mathematics}% !xmpheaddef \xmpheader !xmpnum/{排版数学公式}% !xmpheaddef ~^^{数学} ~%For a spherical triangle with sides $a$, $b$, and $c$, and ~%opposite angles $\alpha$, $\beta$, and $\gamma$, we have: 设球面三角形的三条边长度分别为$a$，$b$ 和 $c$， 它们的对角分别为 $\alpha$，$\beta$ 和 $\gamma$，我们有： ~%$$\cos \alpha = -\cos \beta \cos \gamma + ~% \sin \beta \sin \gamma \cos \alpha \quad ~% \hbox{(Law of Cosines)}$$ $$\cos \alpha = -\cos \beta \cos \gamma + \sin \beta \sin \gamma \cos \alpha \quad \hbox{(余弦定理)}$$ ~%and: 且有： ~%$$\tan {\alpha \over 2} = \sqrt{ ~% {- \cos \sigma \cdot \cos(\sigma - \alpha)} \over ~% {\cos (\sigma - \beta) \cdot \cos (\sigma - \gamma)}},\quad ~% \hbox{where $\sigma = {1 \over 2}(a+b+c)$}$$ $$\tan {\alpha \over 2} = \sqrt{ {- \cos \sigma \cdot \cos(\sigma - \alpha)} \over {\cos(\sigma - \beta) \cdot \cos(\sigma - \gamma)}},\quad \hbox{其中 $\sigma = {1 \over 2}(a+b+c)$}$$ ~%We also have:$$\sin x = {{e^{ix}-e^{-ix}}\over 2i}$$ ~%and: ~%$$\int _0 ^\infty {{\sin ax \sin bx}\over{x^2}}\,dx ~%% The \, above produces a thin space ~% = {\pi a\over 2}, \quad \hbox{if $a < b$}$$ 我们还有：$$\sin x = {{e^{ix}-e^{-ix}}\over 2i}$$ 且有： $$\int _0 ^\infty {{\sin ax \sin bx}\over{x^2}}\,dx % 上面的 \, 生成一个小间隔 = {\pi a\over 2}, \quad \hbox{如果 $a < b$}$$ ~%\noindent The number of combinations ${}_nC_r$ of $n$ ~%things taken $r$ at a time is: \noindent 从 $n$ 个物品中任取 $r$ 个的组合数 ${}_nC_r$ 为： $$C(n,r) = {}_nC_r = {n \choose r} = {{n(n-1) \cdots (n-r+1)} \over {r(r-1) \cdots (1)}} = {{n!!}\over {r!!(n-r)!!}}$$ \noindent ~%The value of the determinant $D$ of order $n$: $n$ 阶行列式 $D$ 的值： $$D = \left|\matrix{a_{11}&a_{12}&\ldots&a_{1n}\cr a_{21}&a_{22}&\ldots&a_{2n}\cr \vdots&\vdots&\ddots&\vdots\cr a_{n1}&a_{n2}&\ldots&a_{nn}\cr}\right| $$ ~%is defined as the sum of $n!!$ terms: 定义为下面$n!!$项的和： $$\sum\>(\pm)\>a_{1i}a_{2j} \ldots a_{nk}$$ ~% The \> above produces a medium space. ~%where $i$, $j$, \dots,~$k$\/ take on all possible values ~%between $1$ and $n$, and the sign of the product is ~%$+$ if the sequence $i$, $j$, \dots,~$k$\/ is an ~%even permutation and $-$ otherwise. Moreover: 其中 $i$, $j$, \dots,~$k$\/ 取遍 $1$ 到 $n$ 的所有可能值， 且当排列 $i$, $j$, \dots,~$k$\/ 为偶置换时乘积取 $+$ 号， 否则取 $-$ 号。此外： $$Q(\xi) = \lambda_1 y_1^2 \sum_{i=2}^n \sum_{j=2}^n y_i b_{ij} y_j,\qquad B = \Vert b_{ij} \Vert = B'$$ \bye ::: ~%\xmpheader !xmpnum/{More mathematics}% !xmpheaddef \xmpheader !xmpnum/{更多数学内容}% !xmpheaddef %^^{math} ^^{数学} ~%The absolute value of $X$, $|x|$, is defined by: ~%$$|x| = \cases{x, &if $x\ge 0$;\cr ~%-x,&otherwise.\cr}$$ ~%Now for some numbered equations. ~%It is the case that for $k \ge 0$: ~%$$x^{k^2}=\overbrace{x\>x\>\cdots\> x}^{2k\ \rm times} ~%\eqno (1)$$ $X$ 的绝对值 $|x|$ 定义为：: $$|x| = \cases{x, &if $x\ge 0$;\cr -x,&otherwise.\cr}$$ 现在写一些标号了的公式。 在 $k \ge 0$ 时，我们有： $$x^{k^2}=\overbrace{x\>x\>\cdots\> x}^{2k\ \rm times} \eqno (1)$$ ~%Here's an example that shows some spacing controls, with ~%a number on the left: 这是一个展示空格间距调整和公式左编号的例子： ~%$$[u]!negthin[v][w]\,[x]\>[y]\;[z]\leqno(2a)$$ $$[u]!negthin[v][w]\,[x]\>[y]\;[z]\leqno(2a)$$ ~%The amount of space between the items in brackets ~%gradually increases from left to right. (We've made ~%the space between the first two items be {\it less\/} ~%than the natural space.) 从做到右公式中的项和括号的距离逐步增大。 （我们把前两项的距离设定得比正常距离 {\it 少\/}。 ~%It is sometimes the case that $$\leqalignno{ ~%u'_1 + tu''_2 &= u'_2 + tu''_1&(2b)\cr ~%\hat\imath &\ne \hat \jmath&(2c)\cr ~%\vec {\vphantom{b}a}&\approx \vec b\cr}$$ ~%% The \vphantom is an invisible rule as tall as a `b'. 有时候， $$\leqalignno{ u'_1 + tu''_2 &= u'_2 + tu''_1&(2b)\cr \hat\imath &\ne \hat \jmath&(2c)\cr \vec {\vphantom{b}a}&\approx \vec b\cr}$$ % \vphantom 是一个不可见的和“b”一样高的盒子。 ~%The result is of order $O(n \log\log n)$. Thus ~%$$\sum_{i=1}^n x_i = x_1+x_2+\cdots+x_n ~%= {\rm Sum}(x_1,x_2,\ldots,x_n). \eqno(3)$$ 结果为 $O(n \log\log n)$. 因此 $$\sum_{i=1}^n x_i = x_1+x_2+\cdots+x_n = {\rm Sum}(x_1,x_2,\ldots,x_n). \eqno(3)$$ ~%and ~%$$dx\,dy = r\,dr\,d\theta!negthin.\eqno(4)$$ ~%The set of all $q$ such that $q\le0$ is written as: ~%$$\{\,q\mid q\le0\, \}$$ 且 $$dx\,dy = r\,dr\,d\theta!negthin.\eqno(4)$$ 满足 $q\le0$ 的所有的 $q$ 可以被写作： $$\{\,q\mid q\le0\, \}$$ ~%Thus ~%$$\forall x\exists y\;P(x,y)\Rightarrow ~%\exists x\exists y\;P(x,y)$$ ~%where ~%$$P(x,y) \buildrel \rm def \over \equiv ~%\hbox{\rm any predicate in $x$ and $y$} . $$ 因此 $$\forall x\exists y\;P(x,y)\Rightarrow \exists x\exists y\;P(x,y)$$ 其中 $$P(x,y) \buildrel \rm def \over \equiv \hbox{\rm 任何一个能够得出 $x$ 和 $y$} . $$ \bye :::