Help:Visualizzare una formula

From Meta, a Wikimedia project coordination wiki
This page is a translated version of the page Help:Displaying a formula and the translation is 23% complete.
Manuale di MediaWiki : Sommario generale —— sommario specifico per Lettori, Scrittori, Amministratori, Sviluppatori —— Altre pagine di aiuto (specifiche per questo progetto)

Questa pagina è una traduzione della corrispondente pagina del manuale in inglese di MediaWiki.

Puoi consultare (in inglese) le linee guida del manuale | la Politica editoriale

{{{{{1}}}}}

MediaWiki uses a subset of TeX markup, including some extensions from LaTeX and AMS-LaTeX, for mathematical formulae. It generates either PNG images or simple HTML markup, depending on user preferences and the complexity of the expression.

More precisely, MediaWiki filters the markup through Texvc, which in turn passes the commands to TeX for the actual rendering. Thus, only a limited part of the full TeX language is supported; see below for details.

To have math rendered, you have to load the Math extension.

Dettagli tecnici

Sintassi

Traditionally, math markup goes inside the XML-style tag math: <math> ... </math>. The old edit toolbar had the button for this, and it is possible to customize the WikiEditor toolbar to add a similar button. The icons are like these: MediaWiki:Math tip and .

However, one can also use parser function #tag: {{#tag:math|...}}; this is more versatile: the wikitext at the dots is first expanded before interpreting the result as TeX code. Thus it can contain parameters, variables, parser functions and templates. Note however that with this syntax double braces in the TeX code must have a space in between, to avoid confusion with their use in template calls etc. Also, to produce the character "|" inside the TeX code, use {{!}}.

In TeX, come nell'HTML, gli spazi aggiuntivi e gli "a capo" sono ingorati

Rendering

The alt text of the PNG images, which is displayed to visually impaired and other readers who cannot see the images, and is also used when the text is selected and copied, defaults to the wikitext that produced the image, excluding the <math> and </math>. You can override this by explicitly specifying an alt attribute for the math element. For example, <math alt="Square root of pi">\sqrt{\pi}</math> generates an image whose alt text is "Square root of pi".

Apart from function and operator names, as is customary in mathematics for variables, letters are in italics; digits are not. For other text, (like variable labels) to avoid being rendered in italics like variables, use \text, \mbox, or \mathrm. You can also define new function names using \operatorname{...}. For example, <math>\text{abc}</math> gives . You can also define new function names using \operatorname{...}.

Caratteri speciali

I simboli seguenti sono caratteri riservati, che hanno un significato speciale in LaTex oppure non sono disponibili in tutti i font.

# $ % ^ & _ { } ~ \

Alcuni di questi possono essere inseriti preceduti da una barra inversa:

<math>\# \$ \% \& \_ \{ \} </math> gives

Altri hanno nomi speciali:

<math> \hat{} \quad \tilde{} \quad \backslash </math>

<span id="TeX_and_HTML">

TeX e HTML

Prima di introdurre il markup in TeX per produrre caratteru speciali, c'è da notare che, come mostra questa tabella comparativa, a volte risultati simili possono essere ottenuti in HTML (vedi Help:Special characters).

TeX Syntax (forcing PNG) TeX Rendering Sintassi HTML HTML Rendering
<math>\alpha</math> {{math|<var>&alpha;</var>}} α
<math> f(x) = x^2\,</math> {{math|''f''(<var>x</var>) {{=}} <var>x</var><sup>2</sup>}} f(x) = x2
<math>\sqrt{2}</math> {{math|{{radical|2}}}} 2
<math>\sqrt{1-e^2}</math> {{math|{{radical|1 &minus; ''e''&sup2;}}}} 1 − e²

I codici a sinistra producono i simboli di destra, ma questi ultimi possono essere anche inseriti direttamente come wikitesto, tranne che per ‘=’.

Sintassi Rendering
&alpha; &beta; &gamma; &delta; &epsilon; &zeta;
&eta; &theta; &iota; &kappa; &lambda; &mu; &nu;
&xi; &omicron; &pi; &rho; &sigma; &sigmaf;
&tau; &upsilon; &phi; &chi; &psi; &omega;
&Gamma; &Delta; &Theta; &Lambda; &Xi; &Pi;
&Sigma; &Phi; &Psi; &Omega;
α β γ δ ε ζ
η θ ι κ λ μ ν
ξ ο π ρ σ ς
τ υ φ χ ψ ω
Γ Δ Θ Λ Ξ Π
Σ Φ Ψ Ω
&int; &sum; &prod; &radic; &minus; &plusmn; &infty;
&asymp; &prop; {{=}} &equiv; &ne; &le; &ge; 
&times; &sdot; &divide; &part; &prime; &Prime;
&nabla; &permil; &deg; &there4; &Oslash; &oslash;
&isin; &notin; 
&cap; &cup; &sub; &sup; &sube; &supe;
&not; &and; &or; &exist; &forall; 
&rArr; &hArr; &rarr; &harr; &uarr; 
&alefsym; - &ndash; &mdash; 
∫ ∑ ∏ √ − ± ∞
≈ ∝ = ≡ ≠ ≤ ≥
× ⋅ ÷ ∂ ′ ″
∇ ‰ ° ∴ Ø ø
∈ ∉ ∩ ∪ ⊂ ⊃ ⊆ ⊇
¬ ∧ ∨ ∃ ∀
⇒ ⇔ → ↔ ↑
ℵ - – —

Il progetto si è sviluppato sia in HTML che in TeX, perchè ciascuno ha i propri vantaggi in certe situazioni.

Vantaggi dell'HTML

  1. Formulas in HTML behave more like regular text. In-line HTML formulae always align properly with the rest of the HTML text and, to some degree, can be cut-and-pasted (this is not a problem if TeX is rendered using MathJax, and the alignment should not be a problem for PNG rendering once bug 32694 is fixed).
  2. The formula’s background and font size match the rest of HTML contents (this can be fixed on TeX formulas by using the commands \pagecolor and \definecolor) and the appearance respects CSS and browser settings while the typeface is conveniently altered to help you identify formulae.
  3. Pages using HTML code for formulae use less data to transmit, which is important to users with slow or capped Internet connections (e.g. those using dialup or mobile Internet connections which are either slow or have a data cap).
  4. Formulae typeset with HTML code will be accessible to client-side script links (a.k.a. scriptlets).
  5. The display of a formula entered using mathematical templates can be conveniently altered by modifying the templates involved; this modification will affect all relevant formulae without any manual intervention.
  6. The HTML code, if entered diligently, will contain all semantic information to transform the equation back to TeX or any other code as needed. It can even contain differences TeX does not normally catch, e.g. {{math|''i''}} for the imaginary unit and {{math|<var>i</var>}} for an arbitrary index variable.
  7. Formulae using HTML code will render as sharp as possible no matter what device is used to render them.

<span id="Pros_of_TeX">

Vantaggi del TeX

  1. TeX is semantically more precise than HTML.
    1. In TeX, "<math>x</math>" means "mathematical variable ", whereas in HTML "x" is generic and somewhat ambiguous.
    2. On the other hand, if you encode the same formula as "{{math|<var>x</var>}}", you get the same visual result x and no information is lost. This requires diligence and more typing that could make the formula harder to understand as you type it. However, since there are far more readers than editors, this effort is worth considering if no other rendering options are available (such as MathJax, which was requested on bug 31406 for use on Wikimedia wikis and is being implemented on Extension:Math as a new rendering option).
  2. One consequence of point 1 is that TeX code can be transformed into HTML, but not vice-versa.[1] This means that on the server side we can always transform a formula, based on its complexity and location within the text, user preferences, type of browser, etc. Therefore, where possible, all the benefits of HTML can be retained, together with the benefits of TeX. It is true that the current situation is not ideal, but that is not a good reason to drop information/contents. It is more a reason to help improve the situation.
  3. Another consequence of point 1 is that TeX can be converted to MathML (e.g. by MathJax) for browsers which support it, thus keeping its semantics and allowing the rendering to be better suited for the reader’s graphic device.
  4. TeX is the preferred text formatting language of most professional mathematicians, scientists, and engineers. It is easier to persuade them to contribute if they can write in TeX.
  5. TeX has been specifically designed for typesetting formulae, so input is easier and more natural if you are accustomed to it, and output is more aesthetically pleasing if you focus on a single formula rather than on the whole containing page.
  6. Once a formula is done correctly in TeX, it will render reliably, whereas the success of HTML formulae is somewhat dependent on browsers or versions of browsers. Another aspect of this dependency is fonts: the serif font used for rendering formulae is browser-dependent and it may be missing some important glyphs. While the browser generally capable to substitute a matching glyph from a different font family, it need not be the case for combined glyphs (compare ‘  ’ and ‘  ’).
  7. When writing in TeX, editors need not worry about whether this or that version of this or that browser supports this or that HTML entity. The burden of these decisions is put on the software. This does not hold for HTML formulae, which can easily end up being rendered wrongly or differently from the editor’s intentions on a different browser.[2]
  8. TeX formulae, by default, render larger and are usually more readable than HTML formulae and are not dependent on client-side browser resources, such as fonts, and so the results are more reliably WYSIWYG.
  9. While TeX does not assist you in finding HTML codes or Unicode values (which you can obtain by viewing the HTML source in your browser), cutting and pasting from a TeX PNG in Wikipedia into simple text will return the LaTeX source.
^  unless your wikitext follows the style of point 1.2
^  The entity support problem is not limited to mathematical formulae though; it can be easily solved by using the corresponding characters instead of entities, as the character repertoire links do, except for cases where the corresponding glyphs are visually indiscernible (e.g. &ndash; for ‘–’ and &minus; for ‘−’).

In some cases it may be the best choice to use neither TeX nor the html-substitutes, but instead the simple ASCII symbols of a standard keyboard (see below, for an example).

Funzioni, simboli e caratteri speciali

Accents/diacritics

\acute{a} \grave{a} \hat{a} \tilde{a} \breve{a}
\check{a} \bar{a} \ddot{a} \dot{a}

Funzioni standard

\sin a \cos b \tan c
\sec d \csc e \cot f
\arcsin h \arccos i \arctan j
\sinh k \cosh l \tanh m \coth n
\operatorname{sh}o\,\operatorname{ch}p\,\operatorname{th}q
\operatorname{arsinh}r\,\operatorname{arcosh}s\,\operatorname{artanh}t
\lim u \limsup v \liminf w \min x \max y
\inf z \sup a \exp b \ln c \lg d \log e \log_{10} f \ker g
\deg h \gcd i \Pr j \det k \hom l \arg m \dim n

Aritmetica modulare

s_k \equiv 0 \pmod{m}
a\,\bmod\,b

Derivatives

\nabla \, \partial x \, dx \, \dot x \, \ddot y\, dy/dx\, \frac{dy}{dx}\, \frac{\partial^2 y}{\partial x_1\,\partial x_2}

Sets

\forall \exists \empty \emptyset \varnothing
\in \ni \not\in \notin \not\ni \subset \subseteq \supset \supseteq
\cap \bigcap \cup \bigcup \biguplus \setminus \smallsetminus
\sqsubset \sqsubseteq \sqsupset \sqsupseteq \sqcap \sqcup \bigsqcup

Operatori

+ \oplus \bigoplus \pm \mp -
\times \otimes \bigotimes \cdot \circ \bullet \bigodot
\star * / \div \frac{1}{2}

Logica

\land (or \and) \wedge \bigwedge \bar{q} \to p
\lor \vee \bigvee \lnot \neg q \And

Root

\sqrt{2} \sqrt[n]{x}

Relations

\sim \approx \simeq \cong \dot= \overset{\underset{\mathrm{def}}{}}{=}
< \le \ll \gg \ge > \equiv \not\equiv \ne \mbox{or} \neq \propto
\lessapprox \lesssim \eqslantless \leqslant \leqq \geqq \geqslant \eqslantgtr \gtrsim \gtrapprox

Geometric

\Diamond \Box \triangle \angle \perp \mid \nmid \| 45^\circ

= Frecce

\leftarrow (or \gets) \rightarrow (or \to) \nleftarrow \nrightarrow \leftrightarrow \nleftrightarrow \longleftarrow \longrightarrow \longleftrightarrow
\Leftarrow \Rightarrow \nLeftarrow \nRightarrow \Leftrightarrow \nLeftrightarrow \Longleftarrow (or \impliedby) \Longrightarrow (or \implies) \Longleftrightarrow (or \iff)
\uparrow \downarrow \updownarrow \Uparrow \Downarrow \Updownarrow \nearrow \searrow \swarrow \nwarrow
\rightharpoonup \rightharpoondown \leftharpoonup \leftharpoondown \upharpoonleft \upharpoonright \downharpoonleft \downharpoonright \rightleftharpoons \leftrightharpoons
\curvearrowleft \circlearrowleft \Lsh \upuparrows \rightrightarrows \rightleftarrows \Rrightarrow \rightarrowtail \looparrowright
\curvearrowright \circlearrowright \Rsh \downdownarrows \leftleftarrows \leftrightarrows \Lleftarrow \leftarrowtail \looparrowleft
\mapsto \longmapsto \hookrightarrow \hookleftarrow \multimap \leftrightsquigarrow \rightsquigarrow

Speciale

\And \eth \S \P \% \dagger \ddagger \ldots \cdots \colon
\smile \frown \wr \triangleleft \triangleright \infty \bot \top
\vdash \vDash \Vdash \models \lVert \rVert \imath \hbar
\ell \mho \Finv \Re \Im \wp \complement
\diamondsuit \heartsuit \clubsuit \spadesuit \Game \flat \natural \sharp

Unsorted (new stuff)

\vartriangle \triangledown \lozenge \circledS \measuredangle \nexists \Bbbk \backprime \blacktriangle \blacktriangledown
\square \blacksquare \blacklozenge \bigstar \sphericalangle \diagup \diagdown \dotplus \Cap \Cup \barwedge
\veebar \doublebarwedge \boxminus \boxtimes \boxdot \boxplus \divideontimes \ltimes \rtimes \leftthreetimes
\rightthreetimes \curlywedge \curlyvee \circleddash \circledast \circledcirc \centerdot \intercal \leqq \leqslant
\eqslantless \lessapprox \approxeq \lessdot \lll \lessgtr \lesseqgtr \lesseqqgtr \doteqdot \risingdotseq
\fallingdotseq \backsim \backsimeq \subseteqq \Subset \preccurlyeq \curlyeqprec \precsim \precapprox \vartriangleleft
\Vvdash \bumpeq \Bumpeq \eqsim \gtrdot
\ggg \gtrless \gtreqless \gtreqqless \eqcirc \circeq \triangleq \thicksim \thickapprox \supseteqq
\Supset \succcurlyeq \curlyeqsucc \succsim \succapprox \vartriangleright \shortmid \between \shortparallel \pitchfork
\varpropto \blacktriangleleft \therefore \backepsilon \blacktriangleright \because \nleqslant \nleqq \lneq \lneqq
\lvertneqq \lnsim \lnapprox \nprec \npreceq \precneqq \precnsim \precnapprox \nsim \nshortmid
\nvdash \nVdash \ntriangleleft \ntrianglelefteq \nsubseteq \nsubseteqq \varsubsetneq \subsetneqq \varsubsetneqq \ngtr
\subsetneq
\ngeqslant \ngeqq \gneq \gneqq \gvertneqq \gnsim \gnapprox \nsucc \nsucceq \succneqq
\succnsim \succnapprox \ncong \nshortparallel \nparallel \nvDash \nVDash \ntriangleright \ntrianglerighteq \nsupseteq
\nsupseteqq \varsupsetneq \supsetneqq \varsupsetneqq
\jmath \surd \ast \uplus \diamond \bigtriangleup \bigtriangledown \ominus
\oslash \odot \bigcirc \amalg \prec \succ \preceq \succeq
\dashv \asymp \doteq \parallel
\ulcorner \urcorner \llcorner \lrcorner
\Coppa\coppa\Digamma\Koppa\koppa\Sampi\sampi\Stigma\stigma\varstigma

Larger expressions

Subscripts, superscripts, integrals

Funzionalità Sintassi Come viene renderizzato
Superscript a^2
Subscript a_2
Grouping a^{2+2}
a_{i,j}
Combining sub & super without and with horizontal separation x_2^3
{x_2}^3
Super super 10^{10^{8}}
Preceding and/or Additional sub & super _nP_k
\sideset{_1^2}{_3^4}\prod_a^b
{}_1^2\!\Omega_3^4
Stacking \overset{\alpha}{\omega}
\underset{\alpha}{\omega}
\overset{\alpha}{\underset{\gamma}{\omega}}
\stackrel{\alpha}{\omega}
Derivatives x', y'', f', f''
x^\prime, y^{\prime\prime}
Derivative dots \dot{x}, \ddot{x}
Underlines, overlines, vectors \hat a \ \bar b \ \vec c
\overrightarrow{a b} \ \overleftarrow{c d} \ \widehat{d e f}
\overline{g h i} \ \underline{j k l}
\not 1 \ \cancel{123}
Frecce A \xleftarrow{n+\mu-1} B \xrightarrow[T]{n\pm i-1} C
Overbraces \overbrace{ 1+2+\cdots+100 }^{\text{sum}\,=\,5050}
Underbraces \underbrace{ a+b+\cdots+z }_{26\text{ terms}}
Somma \sum_{k=1}^N k^2
Sum (force \textstyle) \textstyle \sum_{k=1}^N k^2
Prodotto \prod_{i=1}^N x_i
Prodotto (force \textstyle) \textstyle \prod_{i=1}^N x_i
Coproduct \coprod_{i=1}^N x_i
Coproduct (force \textstyle) \textstyle \coprod_{i=1}^N x_i
Limite \lim_{n \to \infty}x_n
Limite (force \textstyle) \textstyle \lim_{n \to \infty}x_n
Integrale \int\limits_{1}^{3}\frac{e^3/x}{x^2}\, dx
Integral (alternate limits style) \int_{1}^{3}\frac{e^3/x}{x^2}\, dx
Integral (force \textstyle) \textstyle \int\limits_{-N}^{N} e^x\, dx
Integrale (force \textstyle, alternate limits style) \textstyle \int_{-N}^{N} e^x\, dx
Integrale quadruplo \iint\limits_D \, dx\,dy
Integrale triplo \iiint\limits_E \, dx\,dy\,dz
Integrale quadruplo \iiiint\limits_F \, dx\,dy\,dz\,dt
Integrale di linea \int_C x^3\, dx + 4y^2\, dy
Integrale di linea chiusa \oint_C x^3\, dx + 4y^2\, dy
Intersezioni \bigcap_1^n p
Unioni \bigcup_1^k p

Fractions, matrices, multilines

Feature Sintassi How it looks rendered
Fractions \frac{1}{2}=0.5
Small ("text style") fractions \tfrac{1}{2} = 0.5
Large ("display style") fractions \dfrac{k}{k-1} = 0.5
Mixture of large and small fractions \dfrac{ \tfrac{1}{2}[1-(\tfrac{1}{2})^n] }{ 1-\tfrac{1}{2} } = s_n
Continued fractions (note the difference in formatting)
\cfrac{2}{ c + \cfrac{2}{ d + \cfrac{1}{2} } } = a
\qquad
\dfrac{2}{ c + \dfrac{2}{ d + \dfrac{1}{2} } } = a
Binomial coefficients \binom{n}{k}
Small ("text style") binomial coefficients \tbinom{n}{k}
Large ("display style") binomial coefficients \dbinom{n}{k}
Matrices
\begin{matrix}
x & y \\
z & v 
\end{matrix}
\begin{vmatrix}
x & y \\
z & v 
\end{vmatrix}
\begin{Vmatrix}
x & y \\
z & v
\end{Vmatrix}
\begin{bmatrix}
0      & \cdots & 0      \\
\vdots & \ddots & \vdots \\ 
0      & \cdots & 0
\end{bmatrix}
\begin{Bmatrix}
x & y \\
z & v
\end{Bmatrix}
\begin{pmatrix}
x & y \\
z & v 
\end{pmatrix}
\bigl( \begin{smallmatrix}
a&b\\ c&d
\end{smallmatrix} \bigr)
Arrays
\begin{array}{|c|c||c|} a & b & S \\
\hline
0&0&1\\
0&1&1\\
1&0&1\\
1&1&0
\end{array}
Cases
f(n) = 
\begin{cases} 
n/2,  & \mbox{if }n\mbox{ is even} \\
3n+1, & \mbox{if }n\mbox{ is odd} 
\end{cases}
System of equations
\begin{cases}
3x + 5y +  z &= 1 \\
7x - 2y + 4z &= 2 \\
-6x + 3y + 2z &= 3
\end{cases}
Breaking up a long expression so it wraps when necessary
<math>f(x) = \sum_{n=0}^\infty a_n x^n</math>
<math>= a_0 + a_1x + a_2x^2 + \cdots</math>
Multiline equations
\begin{align}
f(x) & = (a+b)^2 \\
& = a^2+2ab+b^2
\end{align}
\begin{alignat}{2}
f(x) & = (a-b)^2 \\
& = a^2-2ab+b^2
\end{alignat}
Multiline equations with aligment specified (left, center, right)
\begin{array}{lcl}
z        & = & a \\
f(x,y,z) & = & x + y + z  
\end{array}
\begin{array}{lcr}
z        & = & a \\
f(x,y,z) & = & x + y + z     
\end{array}

Parenthesizing big expressions, brackets, bars

Feature Sintassi How it looks rendered
male ( \frac{1}{2} )
Buono \left ( \frac{1}{2} \right )

You can use various delimiters with \left and \right:

Feature Sintassi How it looks rendered
Parentesi \left ( \frac{a}{b} \right )
Brackets \left [ \frac{a}{b} \right ] \quad \left \lbrack \frac{a}{b} \right \rbrack
Braces (note the backslash before the braces in the code) \left \{ \frac{a}{b} \right \} \quad \left \lbrace \frac{a}{b} \right \rbrace
Angle brackets \left \langle \frac{a}{b} \right \rangle
Bars and double bars (note: "bars" provide the absolute value function) \left | \frac{a}{b} \right \vert \left \Vert \frac{c}{d} \right \|
Floor and ceiling functions: \left \lfloor \frac{a}{b} \right \rfloor \left \lceil \frac{c}{d} \right \rceil
Slashes and backslashes \left / \frac{a}{b} \right \backslash
Up, down and up-down arrows \left \uparrow \frac{a}{b} \right \downarrow \quad \left \Uparrow \frac{a}{b} \right \Downarrow \quad \left \updownarrow \frac{a}{b} \right \Updownarrow
Delimiters can be mixed, as long as \left and \right are both used \left [ 0,1 \right )
\left \langle \psi \right |

Use \left. or \right. if you don't want a delimiter to appear: \left . \frac{A}{B} \right \} \to X
Size of the delimiters \big( \Big( \bigg( \Bigg( \dots \Bigg] \bigg] \Big] \big]
\big\{ \Big\{ \bigg\{ \Bigg\{ \dots \Bigg\rangle \bigg\rangle \Big\rangle \big\rangle
\big| \Big| \bigg| \Bigg| \dots \Bigg\| \bigg\| \Big\| \big\|
\big\lfloor \Big\lfloor \bigg\lfloor \Bigg\lfloor \dots \Bigg\rceil \bigg\rceil \Big\rceil \big\rceil
\big\uparrow \Big\uparrow \bigg\uparrow \Bigg\uparrow \dots \Bigg\Downarrow \bigg\Downarrow \Big\Downarrow \big\Downarrow
\big\updownarrow \Big\updownarrow \bigg\updownarrow \Bigg\updownarrow \dots \Bigg\Updownarrow \bigg\Updownarrow \Big\Updownarrow \big\Updownarrow
\big / \Big / \bigg / \Bigg / \dots \Bigg\backslash \bigg\backslash \Big\backslash \big\backslash

Alphabets and typefaces

Texvc cannot render arbitrary Unicode characters. Those it can handle can be entered by the expressions below. For others, such as Cyrillic, they can be entered as Unicode or HTML entities in running text, but cannot be used in displayed formulas.

Greek alphabet
\Alpha \Beta \Gamma \Delta \Epsilon \Zeta
\Eta \Theta \Iota \Kappa \Lambda \Mu
\Nu \Xi \Omicron \Pi \Rho \Sigma \Tau
\Upsilon \Phi \Chi \Psi \Omega
\alpha \beta \gamma \delta \epsilon \zeta
\eta \theta \iota \kappa \lambda \mu
\nu \xi \omicron \pi \rho \sigma \tau
\upsilon \phi \chi \psi \omega
\varepsilon \digamma \vartheta \varkappa
\varpi \varrho \varsigma \varphi
Blackboard Bold/Scripts
\mathbb{A} \mathbb{B} \mathbb{C} \mathbb{D} \mathbb{E} \mathbb{F} \mathbb{G}
\mathbb{H} \mathbb{I} \mathbb{J} \mathbb{K} \mathbb{L} \mathbb{M}
\mathbb{N} \mathbb{O} \mathbb{P} \mathbb{Q} \mathbb{R} \mathbb{S} \mathbb{T}
\mathbb{U} \mathbb{V} \mathbb{W} \mathbb{X} \mathbb{Y} \mathbb{Z}
\C \N \Q \R \Z
boldface (vectors)
\mathbf{A} \mathbf{B} \mathbf{C} \mathbf{D} \mathbf{E} \mathbf{F} \mathbf{G}
\mathbf{H} \mathbf{I} \mathbf{J} \mathbf{K} \mathbf{L} \mathbf{M}
\mathbf{N} \mathbf{O} \mathbf{P} \mathbf{Q} \mathbf{R} \mathbf{S} \mathbf{T}
\mathbf{U} \mathbf{V} \mathbf{W} \mathbf{X} \mathbf{Y} \mathbf{Z}
\mathbf{a} \mathbf{b} \mathbf{c} \mathbf{d} \mathbf{e} \mathbf{f} \mathbf{g}
\mathbf{h} \mathbf{i} \mathbf{j} \mathbf{k} \mathbf{l} \mathbf{m}
\mathbf{n} \mathbf{o} \mathbf{p} \mathbf{q} \mathbf{r} \mathbf{s} \mathbf{t}
\mathbf{u} \mathbf{v} \mathbf{w} \mathbf{x} \mathbf{y} \mathbf{z}
\mathbf{0} \mathbf{1} \mathbf{2} \mathbf{3} \mathbf{4}
\mathbf{5} \mathbf{6} \mathbf{7} \mathbf{8} \mathbf{9}
Boldface (greek)
\boldsymbol{\Alpha} \boldsymbol{\Beta} \boldsymbol{\Gamma} \boldsymbol{\Delta} \boldsymbol{\Epsilon} \boldsymbol{\Zeta}
\boldsymbol{\Eta} \boldsymbol{\Theta} \boldsymbol{\Iota} \boldsymbol{\Kappa} \boldsymbol{\Lambda} \boldsymbol{\Mu}
\boldsymbol{\Nu} \boldsymbol{\Xi} \boldsymbol{\Omicron} \boldsymbol{\Pi} \boldsymbol{\Rho} \boldsymbol{\Sigma} \boldsymbol{\Tau}
\boldsymbol{\Upsilon} \boldsymbol{\Phi} \boldsymbol{\Chi} \boldsymbol{\Psi} \boldsymbol{\Omega}
\boldsymbol{\alpha} \boldsymbol{\beta} \boldsymbol{\gamma} \boldsymbol{\delta} \boldsymbol{\epsilon} \boldsymbol{\zeta}
\boldsymbol{\eta} \boldsymbol{\theta} \boldsymbol{\iota} \boldsymbol{\kappa} \boldsymbol{\lambda} \boldsymbol{\mu}
\boldsymbol{\nu} \boldsymbol{\xi} \boldsymbol{\omicron} \boldsymbol{\pi} \boldsymbol{\rho} \boldsymbol{\sigma} \boldsymbol{\tau}
\boldsymbol{\upsilon} \boldsymbol{\phi} \boldsymbol{\chi} \boldsymbol{\psi} \boldsymbol{\omega}
\boldsymbol{\varepsilon} \boldsymbol{\digamma} \boldsymbol{\vartheta} \boldsymbol{\varkappa}
\boldsymbol{\varpi} \boldsymbol{\varrho} \boldsymbol{\varsigma} \boldsymbol{\varphi}
Italics
\mathit{A} \mathit{B} \mathit{C} \mathit{D} \mathit{E} \mathit{F} \mathit{G}
\mathit{H} \mathit{I} \mathit{J} \mathit{K} \mathit{L} \mathit{M}
\mathit{N} \mathit{O} \mathit{P} \mathit{Q} \mathit{R} \mathit{S} \mathit{T}
\mathit{U} \mathit{V} \mathit{W} \mathit{X} \mathit{Y} \mathit{Z}
\mathit{a} \mathit{b} \mathit{c} \mathit{d} \mathit{e} \mathit{f} \mathit{g}
\mathit{h} \mathit{i} \mathit{j} \mathit{k} \mathit{l} \mathit{m}
\mathit{n} \mathit{o} \mathit{p} \mathit{q} \mathit{r} \mathit{s} \mathit{t}
\mathit{u} \mathit{v} \mathit{w} \mathit{x} \mathit{y} \mathit{z}
\mathit{0} \mathit{1} \mathit{2} \mathit{3} \mathit{4}
\mathit{5} \mathit{6} \mathit{7} \mathit{8} \mathit{9}
Roman typeface
\mathrm{A} \mathrm{B} \mathrm{C} \mathrm{D} \mathrm{E} \mathrm{F} \mathrm{G}
\mathrm{H} \mathrm{I} \mathrm{J} \mathrm{K} \mathrm{L} \mathrm{M}
\mathrm{N} \mathrm{O} \mathrm{P} \mathrm{Q} \mathrm{R} \mathrm{S} \mathrm{T}
\mathrm{U} \mathrm{V} \mathrm{W} \mathrm{X} \mathrm{Y} \mathrm{Z}
\mathrm{a} \mathrm{b} \mathrm{c} \mathrm{d} \mathrm{e} \mathrm{f} \mathrm{g}
\mathrm{h} \mathrm{i} \mathrm{j} \mathrm{k} \mathrm{l} \mathrm{m}
\mathrm{n} \mathrm{o} \mathrm{p} \mathrm{q} \mathrm{r} \mathrm{s} \mathrm{t}
\mathrm{u} \mathrm{v} \mathrm{w} \mathrm{x} \mathrm{y} \mathrm{z}
\mathrm{0} \mathrm{1} \mathrm{2} \mathrm{3} \mathrm{4}
\mathrm{5} \mathrm{6} \mathrm{7} \mathrm{8} \mathrm{9}
Fraktur typeface
\mathfrak{A} \mathfrak{B} \mathfrak{C} \mathfrak{D} \mathfrak{E} \mathfrak{F} \mathfrak{G}
\mathfrak{H} \mathfrak{I} \mathfrak{J} \mathfrak{K} \mathfrak{L} \mathfrak{M}
\mathfrak{N} \mathfrak{O} \mathfrak{P} \mathfrak{Q} \mathfrak{R} \mathfrak{S} \mathfrak{T}
\mathfrak{U} \mathfrak{V} \mathfrak{W} \mathfrak{X} \mathfrak{Y} \mathfrak{Z}
\mathfrak{a} \mathfrak{b} \mathfrak{c} \mathfrak{d} \mathfrak{e} \mathfrak{f} \mathfrak{g}
\mathfrak{h} \mathfrak{i} \mathfrak{j} \mathfrak{k} \mathfrak{l} \mathfrak{m}
\mathfrak{n} \mathfrak{o} \mathfrak{p} \mathfrak{q} \mathfrak{r} \mathfrak{s} \mathfrak{t}
\mathfrak{u} \mathfrak{v} \mathfrak{w} \mathfrak{x} \mathfrak{y} \mathfrak{z}
\mathfrak{0} \mathfrak{1} \mathfrak{2} \mathfrak{3} \mathfrak{4}
\mathfrak{5} \mathfrak{6} \mathfrak{7} \mathfrak{8} \mathfrak{9}
Calligraphy/Script
\mathcal{A} \mathcal{B} \mathcal{C} \mathcal{D} \mathcal{E} \mathcal{F} \mathcal{G}
\mathcal{H} \mathcal{I} \mathcal{J} \mathcal{K} \mathcal{L} \mathcal{M}
\mathcal{N} \mathcal{O} \mathcal{P} \mathcal{Q} \mathcal{R} \mathcal{S} \mathcal{T}
\mathcal{U} \mathcal{V} \mathcal{W} \mathcal{X} \mathcal{Y} \mathcal{Z}
Hebrew
\aleph \beth \gimel \daleth
Feature Sintassi How it looks rendered
non-italicised characters \mbox{abc}
mixed italics (bad) \mbox{if} n \mbox{is even}
mixed italics (good) \mbox{if }n\mbox{ is even}
mixed italics (more legible: ~ is a non-breaking space, while "\ " forces a space) \mbox{if}~n\ \mbox{is even}

colore

Equations can use color:

  • {\color{Blue}x^2}+{\color{YellowOrange}2x}-{\color{OliveGreen}1}
  • x_{1,2}=\frac{-b\pm\sqrt{\color{Red}b^2-4ac}}{2a}

See here for all named colors (archived) supported by LaTeX.

Note that color should not be used as the only way to identify something, because it will become meaningless on black-and-white media or for color-blind people. See en:Wikipedia:Manual of Style#Color coding.

Formatting issues

Spacing

Note that TeX handles most spacing automatically, but you may sometimes want manual control.

Feature Sintassi How it looks rendered
double quad space a \qquad b
quad space a \quad b
text space a\ b
text space without PNG conversion a \mbox{ } b
large space a\;b
medium space a\>b [not supported]
small space a\,b
no space ab
small negative space a\!b

Automatic spacing may be broken in very long expressions (because they produce an overfull hbox in TeX):

<math>0+1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+\cdots</math>

This can be remedied by putting a pair of braces { } around the whole expression:

<math>{0+1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+\cdots}</math>

Empty horizontal or vertical spacing

The phantom commands create empty horizontal and/or vertical space the same height and/or width of the argument.

Feature Syntax How it looks rendered
Empty horizontal and vertical spacing \Gamma^{\phantom{i}j}_{i\phantom{j}k}
Empty vertical spacing -e\sqrt{\vphantom{p'}p},\; -e'\sqrt{p'},\; \ldots
Empty horizontal spacing \int u^2\,du=\underline{\hphantom{(2/3)u^3+C}}


Alignment with normal text flow

Due to the default css

img.tex { vertical-align: middle; }

an inline expression like should look good.

If you need to align it otherwise, use <math style="vertical-align:-100%;">...</math> and play with the vertical-align argument until you get it right; however, how it looks may depend on the browser and the browser settings.

Also note that if you rely on this workaround, if/when the rendering on the server gets fixed in future releases, as a result of this extra manual offset your formulae will suddenly be aligned incorrectly. So use it sparingly, if at all.

Commutative diagrams

To make a commutative diagram, there are three steps:

Diagrams in TeX

Xy-pic (online manual) is the most powerful and general-purpose diagram package in TeX.

Simpler packages include:

The following is a template for Xy-pic, together with a hack to increase the margins in dvips, so that the diagram is not truncated by over-eager cropping (suggested in TUGboat TUGboat, Volume 17 1996, No. 3):

\documentclass{amsart}
\usepackage[all, ps]{xy} % <span lang="en" dir="ltr" class="mw-content-ltr">Loading the XY-Pic package</span>
                         % <span lang="en" dir="ltr" class="mw-content-ltr">Using postscript driver for smoother curves</span>
\usepackage{color}       % <span lang="en" dir="ltr" class="mw-content-ltr">For invisible frame</span>
\begin{document}
\thispagestyle{empty} % <span lang="en" dir="ltr" class="mw-content-ltr">No page numbers</span>
\SelectTips{eu}{}     % <span lang="en" dir="ltr" class="mw-content-ltr">Euler arrowheads (tips)</span>
\setlength{\fboxsep}{0pt} % <span lang="en" dir="ltr" class="mw-content-ltr">Frame box margin</span>
{\color{white}\framebox{{\color{black}$$ % <span lang="en" dir="ltr" class="mw-content-ltr">Frame for margin</span>

\xymatrix{ % <span lang="en" dir="ltr" class="mw-content-ltr">The diagram is a 3x3 matrix</span>
%%% <span lang="en" dir="ltr" class="mw-content-ltr">Diagram goes here</span> %%%
}

$$}}} % end math, end frame
\end{document}

If the document class \documentclass[preview]{standalone} is used instead, then the outputted pdf file is automatically cropped.[1]

Convert to SVG

Once you have produced your diagram in LaTeX (or TeX), you can convert it to an SVG file using the following sequence of commands:

pdflatex file.tex
pdfcrop --clip file.pdf tmp.pdf
pdf2svg tmp.pdf file.svg
  (rm tmp.pdf at the end)

pdflatex and the pdfcrop and pdf2svg utilities are needed for this procedure.

If you do not have these programs, you can also use the commands

latex file.tex
dvipdfm file.dvi

to get a PDF version of your diagram.

Programs

In general, you will not be able to get anywhere with diagrams without TeX and Ghostscript, and the inkscape program is a useful tool for creating or modifying your diagrams by hand. There is also a utility pstoedit which supports direct conversion from Postscript files to many vector graphics formats, but it requires a non-free plugin to convert to SVG, and regardless of the format, this editor has not been successful in using it to convert diagrams with diagonal arrows from TeX-created files.

These programs are:

Upload the file

As the diagram is your own work, upload it to Wikimedia Commons, so that all projects (notably, all languages) can use it without having to copy it to their language's Wiki. (If you've previously uploaded a file to somewhere other than Commons, transwiki it to Commons.)

Check size
Before uploading, check that the default size of the image is neither too large nor too small by opening in an SVG application and viewing at default size (100% scaling), otherwise adjust the -y option to dvips.
Name
Make sure the file has a meaningful name.
Upload
Login to Wikimedia Commons, then upload the file; for the Summary, give a brief description.

Now go to the image page and add a description, including the source code, using this template (using {{Information}}):

{{Information

|Description =
{{en| Description [[:en:Link to WP page|topic]]
}}
|Source = {{own}}

Created as per:

[[:en:meta:Help:Displaying a formula#Commutative diagrams]]; source code below.
|Date = The Creation Date, like 1999-12-31
|Author = [[User:YourUserName|Your Real Name]]
|Permission = Public domain; (or other license) see below.
}}

== LaTeX source ==
<source lang="latex">
% LaTeX source here
</source>

== [[Commons:Copyright tags|Licensing]]: ==
{{self|PD-self (or other license)|author=[[User:YourUserName|Your Real Name]]}}

[[Category:Descriptive categories, such as "Group theory"]]
[[Category:Commutative diagrams]]
Source code
  • Include the source code in the image page, in a LaTeX source section, so that the diagram can be edited in future.
  • Include the complete .tex file, not just the fragment, so future editors do not need to reconstruct a compilable file.
License
The most common license for commutative diagrams is PD-self; some use PD-ineligible, especially for simple diagrams, or other licenses. Please do not use the GFDL, as it requires the entire text of the GFDL to be attached to any document that uses the diagram.
Description
If possible, link to a Wikipedia page relevant to the diagram.
Category
Include [[Category:Commutative diagrams]], so that it appears in commons:Category:Commutative diagrams. There are also subcategories, which you may choose to use.
Include image
Now include the image on the original page via [[Image:Diagram.svg]]

Examples

A sample conforming diagram is commons:Image:PSU-PU.svg.

Chemistry

There are two ways to render chemical sum formulae as used in chemical equations:

  • <math chem>
  • <chem>

<chem>X</chem> is short for <math chem>\ce{X}</math>.

(where X is a chemical sum formula)

Technically, <math chem> is a math tag with the extension mhchem enabled, according to the mathjax documentation.

Note, that the commands \cee and \cf are disabled, because they are marked as deprecated in the mhchem LaTeX package documentation.

If the formula reaches a certain "complexity", spaces might be ignored (<chem>A + B</chem> might be rendered as if it were <chem>A+B</chem> with a positive charge). In that case, write <chem>A{} + B</chem> (and not <chem>{A} + {B}</chem> as was previously suggested). This will allow auto-cleaning of formulae once the bug will be fixed and/or a newer mhchem version will be used.

See examples below.

Esempi

=== Chimica

<chem>C6H5-CHO</chem>

<chem>\mathit{A} ->[\ce{+H2O}] \mathit{B}</chem>

<math chem>A \ce{->[\ce{+H2O}]} B</math>

<chem>SO4^2- + Ba^2+ -> BaSO4 v</chem>

<chem>H2NCO2- + H2O <=> NH4+ + CO3^2-</chem>

<chem>H2O</chem>

<chem>Sb2O3</chem>

<chem>H+</chem>

<chem>CrO4^2-</chem>

<chem>AgCl2-</chem>

<chem>[AgCl2]-</chem>

<chem>Y^{99}+</chem>

<chem>Y^{99+}</chem>

<chem>H2_{(aq)}</chem>

<chem>NO3-</chem>

<chem>(NH4)2S</chem>

Quadratic Polynomial



<math>ax^2 + bx + c = 0</math>

Quadratic Polynomial (Force PNG Rendering)



<math>ax^2 + bx + c = 0\,</math>

Quadratic Formula



<math>x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}</math>

Tall Parentheses and Fractions



<math>2 = \left(
 \frac{\left(3-x\right) \times 2}{3-x}
 \right)</math>

 <math>S_{\text{new}} = S_{\text{old}} - \frac{ \left( 5-T \right) ^2} {2}</math>
 

Integrals



<math>\int_a^x \!\!\!\int_a^s f(y)\,dy\,ds
 = \int_a^x f(y)(x-y)\,dy</math>

Summation



<math>\sum_{m=1}^\infty\sum_{n=1}^\infty\frac{m^2\,n}
 {3^m\left(m\,3^n+n\,3^m\right)}</math>

Differential Equation



<math>u'' + p(x)u' + q(x)u=f(x),\quad x>a</math>

Complex numbers



<math>|\bar{z}| = |z|,
 |(\bar{z})^n| = |z|^n,
 \arg(z^n) = n \arg(z)</math>

Limiti



<math>\lim_{z\rightarrow z_0} f(z)=f(z_0)</math>

Integral Equation



<math>\phi_n(\kappa) =
 \frac{1}{4\pi^2\kappa^2} \int_0^\infty
 \frac{\sin(\kappa R)}{\kappa R}
 \frac{\partial}{\partial R}
 \left[R^2\frac{\partial D_n(R)}{\partial R}\right]\,dR</math>

Example



<math>\phi_n(\kappa) = 
 0.033C_n^2\kappa^{-11/3},\quad
 \frac{1}{L_0}\ll\kappa\ll\frac{1}{l_0}</math>

Continuation and cases



<math>
 f(x) =
 \begin{cases}
 1 & -1 \le x < 0 \\
 \frac{1}{2} & x = 0 \\
 1 - x^2 & \mbox{otherwise}
 \end{cases}
 </math>

Prefixed subscript



 <math>{}_pF_q(a_1,\dots,a_p;c_1,\dots,c_q;z)
 = \sum_{n=0}^\infty
 \frac{(a_1)_n\cdots(a_p)_n}{(c_1)_n\cdots(c_q)_n}
 \frac{z^n}{n!}</math>

Fraction and small fraction


<math> \frac {a}{b}\  \tfrac {a}{b} </math>

Bug reports

Discussions, bug reports and feature requests should go to the Wikitech-l mailing list. These can also be filed on Mediazilla under MediaWiki extensions.

Future

In the future, once the MathJax option which was added to the Math extension is stable enough, it may be enabled on Wikimedia wikis (per bug 31406) as a better alternative for the PNG rendering of TeX formulas. MathJax is a JavaScript library for inline rendering of mathematical formulae, and can be used to translate LaTeX into MathML for direct interpretation by the browser.

See also

Note

External links

Sommario delle pagine di Aiuto - Pagine nel namespace Aiuto su: Meta b: n: w: q: wiktionary

Per i lettori: Vai | Ricerche | URL | Namespace | Nomi delle pagine | Sezioni | Collegamenti | Puntano qui | Piped link | Collegamenti Interwiki | Reindirizzamenti | Variabili | Categorie | Pagine speciali
Seguire i cambiamenti: Ultime modifiche | (avanzate) | Cambiamenti correlati | Segui | Cronologia | Confronti | Contributi utenti | Sommario delle modifiche | Modifiche minori | Modifiche sorvegliate
Login e preferenze: Loggarsi | Preferenze | Stile Utente
Editing: Modifica | Nuova pagina | Immagini/file | Pagina delle immagini | Caratteri speciali | Formule | Tabelle | EasyTimeline | Template | Rinominare (muovere) una pagina | Scorciatoie modifiche | Pagine discussioni | Prove || mod_corr_meta |
Altri progetti: Wikibooks | Wikinews | Wikipedia | Wikiquote | Wiktionary
modifica questo piè di pagina