`\DeclareMathAlphabet`

`{`<*math-alph*>`}` `{`<*encoding*>`}` `{`<*family*>`}`
`{`<*series*>`}` `{`<*shape*>`}`

If this is the first declaration for <*math-alph*> then a new math
alphabet with this as its command name is created.
The arguments <*encoding*> <*family*> <*series*> <*shape*> are used to
set, or reset, the default values for this math alphabet in all math
versions; if required, these must be further reset later for a
particular math version by a `\SetMathAlphabet`

command.

If <*shape*> is empty then this <*math-alph*> is declared to be invalid
in all versions, unless it is set by a later `\SetMathAlphabet`

command for a particular math version.
Checks that the command <*math-alph*> is either already a math alphabet
command or is undefined; and that <*sym-font*> is a symbol font.

In these examples, `\foo`

is defined for all math versions but `\baz`

,
by default, is defined nowhere.

\DeclareMathAlphabet{\foo}{OT1}{cmtt}{m}{n} \DeclareMathAlphabet{\baz}{OT1}{}{}{}

`\SetMathAlphabet`

`{`<*math-alph*>`}` `{`<*version*>`}`

`{`<*encoding*>`}` `{`<*family*>`}` `{`<*series*>`}` `{`<*shape*>`}`

Changes, or sets, the font for the math alphabet <*math-alph*> in math
version <*version*> to <*encoding*><*family*><*series*><*shape*>.
Checks that <*math-alph*> has been declared as a math alphabet,
<*version*> is a known math version and <*encoding*> is a known
encoding scheme.

This example defines `\baz`

for the `normal' math version only:

\SetMathAlphabet{\baz}{normal}{OT1}{cmss}{m}{n}Note that this declaration is not used for all math alphabets: Section 3.5 describes

`\DeclareSymbolFontAlphabet`

,
which is used to set up math alphabets contained in fonts which have
been declared as symbol fonts.