出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2016/01/21 23:01:51」(JST)
「latex」はこの項目へ転送されています。ゴムの原料については「ラテックス」をご覧ください。 |
ウィキメディアプロジェクトにおける LaTeX を利用した組版については、「ヘルプ:数式の書き方」の項目をご覧ください。 |
作者 | レスリー・ランポート |
---|---|
初版 | 1980年(36年前) (1980)代初期 |
最新版 | LaTeX2e Issue 20 / 2011年6月27日(4年前) (2011-06-27) |
最新評価版 | LaTeX3 Issue 08 / 2012年7月29日(3年前) (2012-07-29) |
対応OS | クロスプラットフォーム |
対応言語 | 英語他 |
サポート状況 | 開発中 |
種別 | 組版処理、TeXマクロパッケージ |
ライセンス | LPPL(英語版) |
公式サイト | www |
テンプレートを表示 |
LaTeX[1](ラテック、ラテフ、レイテック、レイテックス)とは、レスリー・ランポート(英: Leslie Lamport)によって開発されたテキストベースの組版処理システムである。電子組版ソフトウェア TeX にマクロパッケージを組み込むことによって構築されており、単体の TeX に比べて、より手軽に組版を行うことができるようになっている。
なお、LaTeX を基にアスキーが日本語処理に対応させたものとして日本語 LaTeX が、さらに縦組み処理にも対応させたものとして pLaTeX がある。
LaTeX の生みの親レスリー・ランポートは、「LaTeX」の発音について自著「LaTeX: A Document Preparation System」[2] の中で、
通常、TeX が「テック」と発音されているので、論理的に考えれば「ラーテック」や「ラテック」、「レイテック」などが妥当なところかもしれない。しかし、言葉というものはつねに論理的とはかぎらないので、「レイテックス」でもかまわない。—[3]
と述べている。日本語では「ラテック」あるいは「ラテフ」と呼ばれることが多い。
LaTeX 以前に、「TeX」という名の数式の処理に優れる組版ソフトウェアがあり、その TeX を使ってもっと簡単に論文やレポートを作成したいという要望があった。LaTeX はその要望に応えて開発されたものであり、レスリー・ランポートが TeX の上にマクロパッケージを組み込むことで構築したものである。さらに LaTeX では、TeX の煩雑な部分の修正も行っている(たとえば、累乗根や分数の設定方法など)。また TeX やそれを基にした LaTeX は主に米国での表記法を基に作られたもので、日本の初等教育・中等教育での数式の書き方とは一部異なる[4][5]。例を挙げれば、日本の初等教育・中等教育では等号附き不等号として、「≦」と「≧」が、近似記号として「≒」が、相似記号として「∽」が用いられる。一方で TeX や LaTeX の標準では、等号附き不等号として「≤」(\leq
または \le
)と「≥」(\geq
または \ge
)が、近似記号として「≈」(\approx
) や「∼」(\sim
)、「≃」(\simeq
) が、相似記号として「∼」(\sim
) が用いられる。日本で使われる記号を使う必要がある場合は,amssymbパッケージを用いることで「≦」(\leqq
), 「≧」(\geqq
), 「≒」(\fallingdotseq
) が使用できる。
LaTeX ソフトウェアは、LaTeX Project Public License (LPPL)[6][7]に規定されたライセンスで提供されたフリーソフトウェアである。現在、Mac OS X や Solaris などの UNIX、Linux OS や BSD 系 OS や OpenSolaris などの UNIX 互換 OS、そして Microsoft Windows など、多くの オペレーティングシステム 上で利用できる。
現在使われているバージョンは LaTeX2ε である。古い LaTeX 2.09 を利用している場合には、LaTeX2ε への更新が推奨されている。
なお、組版処理による表記ができないプレーンテキストや電子メールなどの場合には LaTeX2ε () を「LaTeX2e」または「LaTeX 2e」と表記することになっている[9]。また、「pLaTeX2ε」は株式会社アスキーの登録商標であり、「ピーラテックツーイー」と読むのが正しいとされている。
LaTeXでの文書作成と一般的なワープロソフトでの文書作成を比べると以下のような特徴が見られる。
数式組版性能が非常に高いという特徴から、自然科学・応用科学系の中でも数学を多用する分野では学会提出の論文の標準形式として広く用いられている。論文誌に掲載するための体裁を整えたテンプレートの配布を行っている学会もある[15]。一方で化学式を多用する分野ではWord形式を奨励し、LaTeXの使用は一般的でないことがある[16]。
以下は LaTeX 用の入力の例。
\documentclass[12pt]{article}
\title{\LaTeX}
\date{}
\begin{document}
\maketitle \LaTeX{} is a document preparation system for the \TeX{}
typesetting program. It offers programmable desktop publishing
features and extensive facilities for automating most aspects of
typesetting and desktop publishing, including numbering and
cross-referencing, tables and figures, page layout, bibliographies,
and much more. \LaTeX{} was originally written in 1984 by Leslie
Lamport and has become the dominant method for using \TeX; few
people write in plain \TeX{} anymore. The current version is
\LaTeXe.
\newline
% This is a comment, it is not shown in the final output.
% The following shows a little of the typesetting power of LaTeX
\begin{eqnarray}
E &=& mc^2 \\
m &=& \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}
\end{eqnarray}
\end{document}
上記のソースコードを LaTeX で処理することで、以下のような出力が得られる。
以上、“ScienceSoft — LaTeX” に掲載されている例である。
[ヘルプ] |
ウィキブックスに LaTeX 関連の解説書・教科書があります。 |
ウィキメディア・コモンズには、LaTeXに関連するメディアおよびカテゴリがあります。 |
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A latex is a stable dispersion (emulsion) of polymer microparticles in an aqueous medium. Latex itself is natural, but synthetic latexes have been made. Synthetic latexes can be made by polymerizing a monomer such as styrene that has been emulsified with surfactants.
Latex as found in nature is a milky fluid found in 10% of all flowering plants (angiosperms).[1] It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums that coagulate on exposure to air. It is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or scarlet latex. Since the 17th century, latex has been used as a term for the fluid substance in plants.[2] It serves mainly as defense against herbivorous insects.[1] Latex is not to be confused with plant sap; it is a separate substance, separately produced, and with separate functions.
The word is also used to refer to natural latex rubber, particularly non-vulcanized rubber. Such is the case in products like latex gloves, latex condoms and latex clothing. Many people are allergic to rubber latex.
Latex: Colloidal dispersion of polymer particles in a liquid.[3][a]
Synthetic latex: Latex obtained as a product of an emulsion,
mini-emulsion, micro-emulsion, or dispersion polymerization.[3]
The cells (laticifers) in which latex is found make up the laticiferous system, which can form in two very different ways. In many plants, the laticiferous system is formed from rows of cells laid down in the meristem of the stem or root. The cell walls between these cells are dissolved so that continuous tubes, called latex vessels, are formed. Since these vessels are made of many cells, they are known as articulated laticifers. This method of formation is found in the poppy family and in the rubber trees (Para rubber tree, members of the family Euphorbiaceae, members of the mulberry and fig family, such as the Panama rubber tree Castilla elastica), and members of the family Asteraceae. For instance, Parthenium argentatum the guayule plant, is in the tribe Heliantheae; other latex-bearing Asteraceae with articulated laticifers include members of the Cichorieae, a clade whose members produce latex, some of them in commercially interesting amounts. This includes Taraxacum kok-saghyz, a species cultivated for latex production.[4]
In the milkweed and spurge families, on the other hand, the laticiferous system is formed quite differently. Early in the development of the seedling latex cells differentiate, and as the plant grows these latex cells grow into a branching system extending throughout the plant. In many euphorbs, the entire structure is made from a single cell - this type of system is known as a non-articulated laticifer, to distinguish it from the multi-cellular structures discussed above. In the mature plant, the entire laticiferous system is descended from a single cell or group of cells present in the embryo.
The laticiferous system is present in all parts of the mature plant, including roots, stems, leaves, and sometimes the fruits. It is particularly noticeable in the cortical tissues. Latex is usually exuded as a white liquid, but is some cases it can be clear, yellow or red, as in Cannabaceae.[1]
Latex is produced by 20,000 species from over 40 families occurring in multiple lineages in both dicotyledonous and monocotyledonous types of plant. It is also found in conifers and pteridophytes. Among tropical plant species 14% create latex, as opposed to 6% of temperate plant species.[5] Several members of the fungal kingdom also produce latex upon injury, such as Lactarius deliciosus and other milk-caps. This suggests it is the product of convergent evolution and has been selected for on many separate occasions.[1]
Latex functions to protect the plant from herbivores. The idea was first proposed in 1887 by Joseph F. James who noted that latex
... carries with it at the same time such disagreeable properties that it becomes a better protection to the plant from enemies than all the thorns, prickles, or hairs that could be provided. In this plant, so copious and so distasteful has the sap become that it serves a most important purpose in its economy.[6]
Evidence showing this defense function include the finding that slugs will eat leaves drained of their latex but not intact ones, that many insects sever the veins carrying latex before they feed, and that the latex of Asclepias humistrata (sandhill milkweed) kills by trapping 30% of newly hatched monarch butterfly caterpillars.[1]
Other evidence is that latex contains 50–1000× higher concentrations of defense substances than other plant tissues. These toxins include ones that are also toxic to the plant and consist of a diverse range of chemicals that are either poisonous or "antinutritive". Latex is actively moved to the area of injury; in the case of Cryptostegia grandiflora, this can be more than 70 cm.[1]
The clotting property of latex is functional in this defense since it limits wastage and its stickiness traps insects and their mouthparts.[1]
It has been noted that while there exist other explanations for the existence of latex including storage and movement of plant nutrients, waste, and maintenance of water balance that "[e]ssentially none of these functions remain credible and none have any empirical support".[1]
The latex of many species can be processed to produce many materials.
Natural rubber is the most important product obtained from latex; more than 12,000 plant species yield latex containing rubber, though in the vast majority of those species the rubber is not suitable for commercial use.[7] This latex is used to make many other products as well, including mattresses, gloves, swim caps, condoms, catheters and balloons.
Balatá and gutta percha latex contain an inelastic polymer related to rubber.
Latex from the chicle and jelutong trees is used in chewing gum.
Dried latex from the opium poppy is called opium, the source of many useful opiates and other alkaloids of high value[clarification needed].
Synthetic latexes are used in coatings (e.g. latex paint) and glues because they solidify by coalescence of the polymer particles as the water evaporates, and therefore can form films without releasing potentially toxic organic solvents in the environment. Other uses include cement additives, and to conceal information on scratchcards. Latex, usually styrene-based, is also used in immunoassays.
Latex - both synthetic and natural - is used to make mattresses as an alternative to memory foam as it had very similar properties and is preferred as a natural alternative.[8]
Latex is used in many types of clothing. Worn on the body (or applied directly by painting) it tends to be skin-tight, producing a "second skin" effect.
Some people have a serious latex allergy, and exposure to latex products such as latex gloves can cause anaphylactic shock. Guayule latex has only 2% of the levels of protein found in Hevea latexes, and is being researched as a lower-allergen substitute.[9] Additionally, chemical processes may be employed to reduce the amount of antigenic protein in Hevea latex, yielding alternative materials such as Vytex Natural Rubber Latex which provide significantly reduced exposure to latex allergens.
About half of people with spina bifida are also allergic to natural latex rubber, as well as people who have had multiple surgeries, and people who have had prolonged exposure to natural latex.[10]
This section requires expansion. (August 2014) |
Several species of the microbe genera Actinomycetes, Streptomyces, Nocardia, Micromonospora, and Actinoplanes are capable of consuming rubber latex.[11]
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拡張検索 | 「latex hypersensitivity」「latex particle」「latex tube」「latex fixation test」 |
関連記事 | 「late」 |
.