HTML Fragments

This module defines a HTML fragment class, which holds a piece of HTML. This is primarily used in browser-based notebooks, though it might be useful for creating static pages as well.

This module defines MathJax, an object of which performs the task of producing an HTML representation of any object. The produced HTML is renderable in a browser-based notebook with the help of MathJax.

class sage.misc.html.HTMLFragmentFactory

Bases: sage.structure.sage_object.SageObject

eval(s, locals=None)

Evaluate embedded <sage> tags

INPUT:

  • s – string.

  • globals – dictionary. The global variables when evaluating s. Default: the current global variables.

OUTPUT:

A HtmlFragment instance.

EXAMPLES:

sage: a = 123
sage: html.eval('<sage>a</sage>')
\(123\)
sage: html.eval('<sage>a</sage>', locals={'a': 456})
\(456\)
iframe(url, height=400, width=800)

Generate an iframe HTML fragment

INPUT:

  • url – string. A url, either with or without URI scheme (defaults to “http”), or an absolute file path.

  • height – the number of pixels for the page height. Defaults to 400.

  • width – the number of pixels for the page width. Defaults to 800.

OUTPUT:

A HtmlFragment instance.

EXAMPLES:

sage: pretty_print(html.iframe("sagemath.org"))
<iframe height="400" width="800"
src="http://sagemath.org"></iframe>
sage: pretty_print(html.iframe("http://sagemath.org",30,40))
<iframe height="30" width="40"
src="http://sagemath.org"></iframe>
sage: pretty_print(html.iframe("https://sagemath.org",30))
<iframe height="30" width="800"
src="https://sagemath.org"></iframe>
sage: pretty_print(html.iframe("/home/admin/0/data/filename"))
<iframe height="400" width="800"
src="file:///home/admin/0/data/filename"></iframe>
sage: pretty_print(html.iframe('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAA'
....: 'AUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBA'
....: 'AO9TXL0Y4OHwAAAABJRU5ErkJggg=="'))
<iframe height="400" width="800"
src="http://data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==""></iframe>
class sage.misc.html.HtmlFragment

Bases: str, sage.structure.sage_object.SageObject

A HTML fragment.

This is a piece of HTML, usually not a complete document. For example, just a <div>...</div> piece and not the entire <html>...</html>.

EXAMPLES:

sage: from sage.misc.html import HtmlFragment
sage: HtmlFragment('<b>test</b>')
<b>test</b>
_rich_repr_(display_manager, **kwds)

Rich Output Magic Method

See sage.repl.rich_output for details.

EXAMPLES:

sage: from sage.repl.rich_output import get_display_manager
sage: dm = get_display_manager()
sage: h = sage.misc.html.HtmlFragment('<b>old</b>')
sage: h._rich_repr_(dm)  # the doctest backend does not support html
OutputPlainText container
class sage.misc.html.MathJax

Bases: object

Render LaTeX input using MathJax. This returns a MathJaxExpr.

EXAMPLES:

sage: from sage.misc.html import MathJax
sage: MathJax()(3)
<html>\[3\]</html>
sage: MathJax()(ZZ)
<html>\[\newcommand{\Bold}[1]{\mathbf{#1}}\Bold{Z}\]</html>
eval(x, globals=None, locals=None, mode='display', combine_all=False)

Render LaTeX input using MathJax. This returns a MathJaxExpr.

INPUT:

  • x - a Sage object

  • globals - a globals dictionary

  • locals - extra local variables used when evaluating Sage code in x.

  • mode - string (optional, default 'display'):

    'display' for displaymath, 'inline' for inline math, or 'plain' for just the LaTeX code without the surrounding html and script tags.

  • combine_all - boolean (Default: False): If combine_all is True and the input is a tuple, then it does not return a tuple and instead returns a string with all the elements separated by a single space.

OUTPUT:

A MathJaxExpr

EXAMPLES:

sage: from sage.misc.html import MathJax
sage: MathJax().eval(3, mode='display')
<html>\[3\]</html>
sage: MathJax().eval(3, mode='inline')
<html>\(3\)</html>
sage: MathJax().eval(type(3), mode='inline')
<html>\(\verb|&lt;class|\verb| |\verb|'sage.rings.integer.Integer'>|\)</html>
class sage.misc.html.MathJaxExpr(y)

Bases: object

An arbitrary MathJax expression that can be nicely concatenated.

EXAMPLES:

sage: from sage.misc.html import MathJaxExpr
sage: MathJaxExpr("a^{2}") + MathJaxExpr("x^{-1}")
a^{2}x^{-1}
sage.misc.html.html(obj, concatenate=True, strict=False)

Construct a HTML fragment

INPUT:

  • obj – anything. An object for which you want an HTML representation.

  • concatenate – if True, combine HTML representations of elements of the container obj

  • strict – if True, construct an HTML representation of obj even if obj is a string

OUTPUT:

A HtmlFragment instance.

EXAMPLES:

sage: h = html('<hr>');  pretty_print(h)
<hr>
sage: type(h)
<class 'sage.misc.html.HtmlFragment'>

sage: html(1/2)
<html>\(\displaystyle \frac{1}{2}\)</html>

sage: html('<a href="http://sagemath.org">sagemath</a>')
<a href="http://sagemath.org">sagemath</a>

sage: html('<a href="http://sagemath.org">sagemath</a>', strict=True)
<html>\(\displaystyle \verb|&lt;a|\verb| |\verb|href="http://sagemath.org">sagemath&lt;/a>|\)</html>

Display preference align_latex affects rendering of LaTeX expressions:

sage: from sage.repl.rich_output.display_manager import get_display_manager
sage: dm = get_display_manager()
sage: dm.preferences.align_latex = 'left'
sage: html(1/2)
<html>\(\displaystyle \frac{1}{2}\)</html>
sage: dm.preferences.align_latex = 'center'
sage: html(1/2)
<html>\[\frac{1}{2}\]</html>
sage: dm.preferences.align_latex = None  # same with left
sage: html(1/2)
<html>\(\displaystyle \frac{1}{2}\)</html>
sage.misc.html.math_parse(s)

Transform the string s with TeX maths to an HTML string renderable by MathJax.

INPUT:

  • s – a string

OUTPUT:

A HtmlFragment instance.

Specifically this method does the following:

  • Replace all $text$'s by \(text\)

  • Replace all $$text$$'s by \[text\]

  • Replace all $'s by $'s. Note that this has precedence over the above two cases.

EXAMPLES:

sage: print(sage.misc.html.math_parse('This is $2+2$.'))
This is \(2+2\).
sage: print(sage.misc.html.math_parse('This is $$2+2$$.'))
This is \[2+2\].
sage: print(sage.misc.html.math_parse('This is \\[2+2\\].'))
This is \[2+2\].
sage: print(sage.misc.html.math_parse(r'$2+2$ is rendered to $2+2$.'))
<span>$</span>2+2<span>$</span> is rendered to \(2+2\).
sage.misc.html.pretty_print_default(enable=True)

Enable or disable default pretty printing.

Pretty printing means rendering things in HTML and by MathJax so that a browser-based frontend can render real math.

This function is pretty useless without the notebook, it should not be in the global namespace.

INPUT:

  • enable – bool (optional, default True). If True, turn on pretty printing; if False, turn it off.

EXAMPLES:

sage: pretty_print_default(True)
sage: 'foo'  # the doctest backend does not support html
'foo'
sage: pretty_print_default(False)
sage: 'foo'
'foo'