mathbfit

The bold italic math alphabet is named \mathbfit like in unicode-math (with an alias \mathbold like in fixmath and related packages). With the reuseMathAlphabets option, the roman bold math alphabet \mathbf is redefined and \mathbfit made an alias. The series selector bx (bold extended) is used, because it is better supported than b. (Is there any LaTeX math font distinguishing between b and bx?)

\ifisomath@reuseMathAlphabets
  \DeclareMathAlphabet{\mathbf}{OML}{\isomath@rmdefault}{bx}{it}
  \def\mathbfit{\mathbf}
\else
  \DeclareMathAlphabet{\mathbfit}{OML}{\isomath@rmdefault}{bx}{it}
\fi

alias (overwriting the definition from fixmath):

\renewcommand*{\mathbold}{\mathbfit}

mathsfit

For sans-serif italic, we define a new alphabet \mathsfit (with the alias \mathsans in analogy to \mathbold). As this typeface is not required by ISO 80000-2 and TeX limits the number of math alphabets to 16 per math version, it is only defined if the OMLmathsfit or OMLmathsans option is set:

\ifisomath@OMLmathsfit
  \DeclareMathAlphabet{\mathsfit}{OML}{\isomath@sfdefault}{m}{it}
  \SetMathAlphabet{\mathsfit}{bold}{OML}{\isomath@sfdefault}{bx}{it}
  \def\mathsans{\mathsfit}
\fi

mathsfbfit

The sans serif bold italic alphabet is used for tensor symbols. Following the Unicode naming scheme it is called \mathsfbfit``(with the backwards compatibility alias ``\mathboldsans). With the reuseMathAlphabets option, the upright sans serif math alphabet \mathsf is redefined and \mathsfbfit made an alias to it:

\ifisomath@reuseMathAlphabets
  \DeclareMathAlphabet{\mathsf}{OML}{\isomath@sfdefault}{bx}{it}
  \def\mathsfbfit{\mathsf}
\else
  \DeclareMathAlphabet{\mathsfbfit}{OML}{\isomath@sfdefault}{bx}{it}
\fi
\def\mathboldsans{\mathsfbfit}

Redefine standard alphabets

Redefine standard alphabets in OML font encoding if the corresponding OMLmath* option is true:

\ifisomath@OMLmathrm
  \SetMathAlphabet{\mathrm}{normal}{OML}{\isomath@rmdefault}{m}{n}
  \SetMathAlphabet{\mathrm}{bold}{OML}{\isomath@rmdefault}{bx}{n}
\fi
\ifisomath@OMLmathbf
  \SetMathAlphabet{\mathbf}{normal}{OML}{\isomath@rmdefault}{bx}{n}
\fi
\ifisomath@OMLmathsf
  \SetMathAlphabet{\mathsf}{normal}{OML}{\isomath@sfdefault}{m}{n}
  \SetMathAlphabet{\mathsf}{bold}{OML}{\isomath@sfdefault}{bx}{n}
\fi
\ifisomath@OMLmathtt
  \SetMathAlphabet{\mathtt}{normal}{OML}{\ttdefault}{m}{n}
  \SetMathAlphabet{\mathtt}{bold}{OML}{\ttdefault}{bx}{n}
\fi

\vectorsym

Alphabetic vectors symbols are typeset boldface italic while numeric ones (e.g. zero vector) are typeset boldface upright. The number test is a simplified version from the LaTeX FAQ "Is the argument a number?" It fails if a number is followed by a non-number, e.g. \vectorsym{1a}, but this is no valid vector symbol and would look strange with the \vec accent, too.

\providecommand*{\vectorsym}[1]{%
  \ifnum9<1#1%
    \mathbf{#1}%
  \else%
    \mathbfit{#1}%
  \fi}

For easier writing or to make existing documents conform to the standard, you might want to re-define the standard \vec command after loading this package.

\matrixsym

Symbols for matrices are typeset boldface italic, i. e. in the same face as vectors.

\providecommand*{\matrixsym}{\vectorsym}

\tensorsym

Symbols for tensors are sans-serif bold italic:

\providecommand*{\tensorsym}{\mathsfbfit}

Unknown makro in font definition file

The Kepler Sans font definition file omljkpss.fd contains a boolean that is defined in kpfonts.sty. This leads to errors if the fonts are used from another package. Provide a dummy definition:

\newif\ifkp@upRm

Common family name for text and math fonts

Some font packages provide matching text and math font but do not define a substitution in their *.fd files. Ideally, the following mappings should be moved there.

Mathpazo (Palatino) ppl ↔ zplm

\DeclareFontFamily{OML}{ppl}{\skewchar\font127}
\DeclareFontShape{OML}{ppl}{m}{it}{<-> ssub * zplm/m/it}{}
\DeclareFontShape{OML}{ppl}{bx}{it}{<-> ssub * zplm/b/it}{}

Scaling

Scale the fav (Arev), iwona, jkpss (Kepler Sans) and llcmss (LX Fonts) sans serif fonts by the value of the scaled option.

To get scaled versions of a font, you cannot use the ssub size function, but must use the empty function or s with the font file as argument [found by experiment, GM 2010-01-28].

Arev (see omlzavm.fd) fav ↔ zavm:

\DeclareFontFamily{OML}{fav}{\skewchar\font127}
\DeclareFontShape{OML}{fav}{m}{it}{<-> s * [\isomath@scaled] zavmri7m}{}
\DeclareFontShape{OML}{fav}{bx}{it}{<-> s * [\isomath@scaled] zavmbi7m}{}

Iwona (see omliwona.fd) iwona ↔ mi-iwona:

\DeclareFontFamily{OML}{iwona}{}
\DeclareFontShape{OML}{iwona}{m}{it}{<-> s * [\isomath@scaled] mi-iwonari}{}
\DeclareFontShape{OML}{iwona}{bx}{it}{<-> s * [\isomath@scaled] mi-iwonabi}{}

Kepler Serif (see omljkpss.fd):

\DeclareFontFamily{OML}{jkpss}{\skewchar\font127 }
\DeclareFontShape{OML}{jkpss}{m}{it}{<-> s * [\isomath@scaled] jkpssmi}{}
\DeclareFontShape{OML}{jkpss}{bx}{it}{<-> s * [\isomath@scaled] jkpssbmi}{}

LX Fonts (see lxfonts.sty) llcmss ↔ llcmm:

\DeclareFontFamily{OML}{llcmss}{\skewchar\font'177}
\DeclareFontShape{OML}{llcmss}{m}{it}{<-> s * [\isomath@scaled] lcmmi8}{}
\DeclareFontShape{OML}{llcmss}{bx}{it}{<-> s * [\isomath@scaled] lcmmib8}{}