Math equations

latexToOmml and mathmlToOmml from pptx-ts/math convert an equation to OMML, the markup PowerPoint's equation editor stores. Pass the result to the math option of a text item and the slide gets an equation you can edit in PowerPoint.

import TsPptx from 'pptx-ts'
import { latexToOmml } from 'pptx-ts/math'

const pptx = new TsPptx()
const slide = pptx.addSlide()

slide.addText([{ math: latexToOmml('x = \\frac{-b \\pm \\sqrt{b^2 - 4ac}}{2a}') }], { x: 1, y: 2, w: 8, h: 1 })

await pptx.writeFile({ fileName: 'quadratic.pptx' })

A math item ignores any text on the same item. Without inline: true it is also its own centered paragraph.

Install the converters

The two converters are optional peer dependencies, so a project that never writes math does not carry them. Install both to use pptx-ts/math:

npm install temml mathml2omml

Package	Converts	License
temml	LaTeX to MathML	MIT
mathml2omml	MathML to OMML	LGPL-3.0-or-later

mathml2omml is never bundled into this package's output. It stays a separate, replaceable package in your node_modules. A project whose policy rules out LGPL code can leave it uninstalled and pass OMML to math directly.

pptx-ts/math runs only under Node, because it loads the converters synchronously through Node's createRequire. The OMML it returns is a plain string: store it, and pass it to math in any runtime.

Functions at a glance

Function	Option	Returns	Usable inline
latexToOmml(latex)	display omitted or true	A centered display block, <m:oMathPara>	Prefer display: false. With inline: true the block's centering wrapper is dropped.
latexToOmml(latex, { display: false })	display: false	A bare equation, <m:oMath>, rendered in inline mode	Yes
mathmlToOmml(mathml)	none	A bare equation, <m:oMath>	Yes

Neither function puts namespace declarations in its result: the math option declares them.

The text item takes the result through two options:

Option	Type	Default	Effect
math	string	none	OMML: a whole <m:oMathPara>, a whole <m:oMath>, or the contents of one.
inline	boolean	false	Flow the equation between the neighbouring text runs instead of giving it its own centered paragraph. No effect without math.

Flow an equation inside a sentence

Set inline: true on the item and give it the bare form:

slide.addText(
  [
    { text: 'where ' },
    { math: latexToOmml('x^2+1=y', { display: false }), inline: true },
    { text: ' holds' },
  ],
  { x: 1, y: 1, w: 8, h: 1 }
)

The equation shares one paragraph with the text on either side of it.

Convert MathML

import { mathmlToOmml } from 'pptx-ts/math'

slide.addText(
  [{ math: mathmlToOmml('<math><msup><mi>e</mi><mi>x</mi></msup></math>') }],
  { x: 1, y: 3, w: 8, h: 1 }
)

mathmlToOmml converts your MathML as written. An <mover> becomes an accent only when it states accent="true", and without it the <mover> becomes an upper limit.

Handle invalid LaTeX

latexToOmml throws on LaTeX that temml cannot parse, rather than returning a broken equation. The message carries temml's parse position when temml reports one, as in Invalid LaTeX (position 6): .... Catch it when the input comes from users:

import { InvalidOptionError, latexToOmml } from 'pptx-ts/math'

function toOmml(latex: string): string | null {
  try {
    return latexToOmml(latex)
  } catch (err) {
    if (err instanceof InvalidOptionError && err.code === 'math/invalid-latex') return null
    throw err
  }
}

What each LaTeX construct becomes

latexToOmml maps these constructs to these PowerPoint equation objects:

LaTeX	Equation object
\frac	Fraction (m:f)
\sqrt, \sqrt[n]	Radical (m:rad)
\sum, \int	N-ary operator (m:nary)
x^2, x_i, x_i^2	Superscript, subscript, both (m:sSup, m:sSub, m:sSubSup)
\lim_{x \to 0}	Subscript (m:sSub), not a lower limit
pmatrix, cases	Matrix (m:m)
\hat, \^, \tilde, \~, \acute, \', \grave, \`, \ddot, \", \dot, \., \bar, \=, \breve, \u, \check, \v, \mathring, \r, \H, \vec, \dddot	Accent (m:acc), carrying the combining mark Word writes
\widehat, \overrightarrow, \overgroup, \overbrace, \underbrace	Group character (m:groupChr)
\overline, \underline	Border box (m:borderBox)
\stackrel, \xrightarrow	Upper limit (m:limUpp)
\utilde and other under-accents	Lower limit (m:limLow). OMML has no accent object that sits below its base.
\ddddot	Upper limit (m:limUpp). Its four-dot mark is two characters, and an accent holds one.
\left( x \right)	Plain bracket characters, not a delimiter object

The accent rows describe latexToOmml. mathmlToOmml follows the accent attribute in your MathML instead.

Invalid input

Condition	Warns or throws	Code
LaTeX temml cannot parse, such as \frac{ or an unknown command	throws	InvalidOptionError math/invalid-latex
temml or mathml2omml is not installed	throws on the first call	UnsupportedFeatureError math/missing-optional-peer
An empty LaTeX string	returns an empty equation, no error	none
A string with no <math> element, or MathML that converts to no equation, passed to mathmlToOmml	throws	InvalidOptionError math/invalid-mathml

Limits

• The converters run only under Node. The OMML string they return works anywhere.
• LaTeX goes to temml as given: no custom macros, no \usepackage, and no environment temml does not support.
• An equation needs a reader that understands PowerPoint 2010's a14 extension. There is no image fallback, and a reader without the extension skips the whole text box.
• Beyond the table above, how an equation looks is up to temml and mathml2omml.

See also

• TextProps, for math and inline
• Errors and warnings