Subscripts and superscripts

To make subscripts and superscripts, use the '_' and '^' symbols:

r'$\alpha_i > \beta_i$'

Some symbols automatically put their sub/superscripts under and over the operator. For example, to write the sum of x_i from 0 to ∞, you could do:

r'$\sum_{i=0}^\infty x_i$'

Fractions

Fractions can be created with the \frac{}{} command:

r'$\frac{3}{4}$'

produces

Fractions can be arbitrarily nested:

r'$\frac{5 - \frac{1}{x}}{4}$'

produces

Note that special care needs to be taken to place parentheses and brackets around fractions. Doing things the obvious way produces brackets that are too small:

r'$(\frac{5 - \frac{1}{x}}{4})$'

The solution is to precede the bracket with \left and \right to inform the parser that those brackets encompass the entire object:

r'$\left(\frac{5 - \frac{1}{x}}{4}\right)$'

Radicals

Radicals can be produced with the \sqrt[]{} command. For example:

r'$\sqrt{2}$'

Any base can (optionally) be provided inside square brackets. Note that the base must be a simple expression, and can not contain layout commands such as fractions or sub/superscripts:

r'$\sqrt[3]{x}$'

Fonts

The default font is italics for mathematical symbols. To change fonts, eg, to write "sin" in a Roman font, enclose the text in a font command:

r'$s(t) = \mathcal{A}\mathrm{sin}(2 \omega t)$'

More conveniently, many commonly used function names that are typeset in a Roman font have shortcuts. So the expression above could be written as follows:

r'$s(t) = \mathcal{A}\sin(2 \omega t)$'

Here "s" and "t" are variable in italics font (default), "sin" is in Roman font, and the amplitude "A" is in calligraphy font. Note in the example above the caligraphy A is squished into the sin. You can use a spacing command to add a little whitespace between them:

s(t) = \mathcal{A}\/\sin(2 \omega t)

The choices available with all fonts are:

Command	Result
\mathrm{Roman}	Roman
\mathit{Italic}	Italic
\mathtt{Typewriter}	Typewriter
\mathcal{CALLIGRAPHY}	CALLIGRAPHY

When using the STIX fonts, you also have the choice of:

Command	Result
\mathbb{blackboard}	:math-stix:`\mathbb{blackboard}`
\mathrm{\mathbb{blackboard}}	:math-stix:`\mathrm{\mathbb{blackboard}}`
\mathfrak{Fraktur}	:math-stix:`\mathfrak{Fraktur}`
\mathsf{sansserif}	:math-stix:`\mathsf{sansserif}`
\mathrm{\mathsf{sansserif}}	:math-stix:`\mathrm{\mathsf{sansserif}}`

There are also three global "font sets" to choose from, which are selected using the mathtext.fontset parameter in :ref:`matplotlibrc <matplotlibrc-sample>`.

cm: Computer Modern (TeX)

stix: STIX (designed to blend well with Times)

stixsans: STIX sans-serif

Accents

An accent command may precede any symbol to add an accent above it. There are long and short forms for some of them.

Command	Result
\acute a or \'a	á
\bar a	‒a
\breve a	ă
\ddot a or \"a	ä
\dot a or \.a	ȧ
\grave a or \`a	à
\hat a or \^a	â
\tilde a or \~a	ã
\vec a	→a

In addition, there are two special accents that automatically adjust to the width of the symbols below:

Command	Result
\widehat{xyz}	^xyz
\widetilde{xyz}	～xyz

Care should be taken when putting accents on lower-case i's and j's. Note that in the following \imath is used to avoid the extra dot over the i:

r"$\hat i\ \ \hat \imath$"

Symbols

You can also use a large number of the TeX symbols, as in \infty, \leftarrow, \sum, \int.

If a particular symbol does not have a name (as is true of many of the more obscure symbols in the STIX fonts), Unicode characters can also be used:

ur'$\u23ce$'

Example

Here is an example illustrating many of these features in context.