\bra - LaTeX bra-ket command

\bra a

Renderer support

Package	MathJax	KaTeX	XeTeX
`braket`	MathJax: Full	KaTeX: Full	XeTeX: None
`physics`	MathJax: Full	KaTeX: Full	XeTeX: Full

Syntax#

\bram{a}math content

Argspec m — one mandatory argument. In braket. Reading argspecs

\bras*starm{a}math content

Argspec s m — one optional and one mandatory argument. In physics. Reading argspecs

physics

\bra{a}

physics

\bra*{\psi}

Package	Signature	Allowed mode	Notes
`braket`	`m`	math	Used in Dirac bra-ket notation to denote a bra vector in quantum mechanics expressions.
`physics`	`s m`	math	Used to denote a bra vector in quantum mechanics.

TeXForm parses this entry as prefix syntax; the package determines its argument specification.

\bra{#1} {\langle {#1} \vert}

MathJax reads #1 with GetArgument, so a single token can be used without braces.

\bra{#1} \left\langle{#1}\right\vert{}

If starred (\bra*{#1}), expands to \langle{#1}\vert. If immediately followed by \ket{...}, merges into a combined bra-ket representation.

Expand bra to an explicit angle-bracket and bar fence form.

\bra{#1} \left\langle #1 \right\vert

{\langle {#1} \vert}exact
\langle #1 \vertapproximate
Equivalent to the starred form \bra*{#1}.
\left\langle #1 \right\vertapproximate
Equivalent to the unstarred form, ignoring the trailing empty group.

`braket`
Input	Case	MathJax	KaTeX	XeTeX
`\bra{a}`	Positive · baseline	Pass	Pass	Fail
`\bra a`	Positive · bare[0]	Pass	Pass	Fail

`physics`
Input	Case	MathJax	KaTeX	XeTeX
`\bra{a}`	Positive · baseline	Pass	Pass	Pass
`\bra*{a}`	Positive · vary:s[0]	Pass	Pass	Pass
`\bra a`	Positive · bare[1]	Pass	Pass	Pass