Cannot use the `\subfloat` command when compiled with TeX Live 2015

[xyguo]

Problem description:

When using the \subfloat to place multiple image in one figure environment, the following problem occurs:

! Undefined control sequence.
\in@ #1#2->\begingroup \def \in@@
                                  ##1#1{}\toks@ \expandafter {\in@@ #2{}{}#1...
l.7   \subfloat
               [A]{

---

System environment:

OS: macOS Sierra 10.12.3

$ uname -v
Darwin Kernel Version 16.4.0: Thu Dec 22 22:53:21 PST 2016; root:xnu-3789.41.3~3/RELEASE_X86_64

$ tex --version
TeX 3.14159265 (TeX Live 2015)
kpathsea version 6.2.1
Copyright 2015 D.E. Knuth.

$ xelatex --version
XeTeX 3.14159265-2.6-0.99992 (TeX Live 2015)
kpathsea version 6.2.1
Copyright 2015 SIL International, Jonathan Kew and Khaled Hosny.

---

Minimal example to reproduce the problem

$ ls
gbt7714-2005.bst   njuname.eps        njuthesis.cls      test_njuthesis.log
njulogo.eps              njuthesis.cfg        test_njuthesis.tex

The test_njuthesis.tex is written as follows:

\documentclass[master, macfonts, draft]{njuthesis}

\begin{document}

\begin{figure}[!htbp]
  \centering
  \subfloat[A]{
    \includegraphics[width=0.41\textwidth]{A.pdf}
  }
  \hfill
  \subfloat[B]{
    \includegraphics[width=0.41\textwidth]{B.pdf}
  }
  \caption{\small AAA \label{fig:AAA}}
\end{figure}

\end{document}

---

Additional info

I also post the same question on TeX Stackexchange. Hope there would be some useful answers.

[jackyangNJ]

@xyguo Hi, I have also met this problem, have you solved it?

[xyguo]

@jackyangNJ No, seems that we have to modify the template file a lot to solve this problem. So at the end I use subcaption instead. Below is a example:

%%load package
\usepackage{caption}
\usepackage{subcaption}

%%example
\begin{figure}[!htbp]
  \centering
  \subcaptionbox{\footnotesize {Pos.-Acc.}}{
    \includegraphics[width=0.45\textwidth]{figures/fig-crv-bp/pose_accessory_2.pdf}
  }
  \hfill
  \subcaptionbox{\footnotesize {Pos.-Exp.}}{
    \includegraphics[width=0.45\textwidth]{figures/fig-crv-bp/pose_expression_2.pdf}
  }
  \\
  \subcaptionbox{\footnotesize {WIKI-Acc.}}{
    \includegraphics[width=0.45\textwidth]{figures/fig-crv-bp/wiki_accessory_2.pdf}
  }
  \hfill
  \subcaptionbox{\footnotesize {WIKI-Exp.}}{
    \includegraphics[width=0.45\textwidth]{figures/fig-crv-bp/wiki_expression_2.pdf}
  }
  \caption{\small XXX\label{fig:model-number-influence}}
\end{figure}

[jackyangNJ]

@xyguo Thanks a lot!