[Tex/LaTex] When using unicode-math, how to get the original calligraphic alphabet back

fontssymbolsunicode-mathxetex

I am happy with the great majority of what unicode-math does. But at times I find that I prefer a symbol the way it was before. With \varnothing and \complement, for example. In those cases I was able to save them under a different name before loading unicode-math, but this doesn't always work.

Right now I'm trying to access the \mathcal alphabet from plain LaTeX. How might I accomplish this?


Additional Question

I've been looking through unicode-math, trying to figure out where exactly the original \mathcal alphabet gets discarded, but I eventually gave up.

It would be interesting if someone could explain:

  • how/where the original \mathcal font is defined anyway, and
  • what kind of 'switch' is thrown by unicode-math that makes it unavailable.

Best Answer

Just override the declarations with the original one:

\documentclass{article}

\usepackage{unicode-math}

\DeclareMathAlphabet{\mathcal}{OMS}{cmsy}{m}{n}

\begin{document}
$\mathcal{DFIP}_{\mathcal{DFIP}_{\mathcal{DFIP}}}$
\end{document}

enter image description here

This is the output of pdffonts, showing that cmsy is used.

name                                 type              encoding         emb sub uni object ID
------------------------------------ ----------------- ---------------- --- --- --- ---------
GQWLIO+CMSY10                        Type 1C           Builtin          yes yes no       4  0
NCPDNV+CMSY7                         Type 1C           Builtin          yes yes no       5  0
BZNGBB+CMSY5                         Type 1C           Builtin          yes yes no       6  0
MMERCJ+LMRoman10-Regular-Identity-H  CID Type 0C       Identity-H       yes yes yes      8  0