在嵌套的多项式中求指数

Question

基于赫伯特的回答这问题，我做了以下工作：

\documentclass[pstricks, border=0pt]{standalone}
\usepackage{pst-solides3d}

\begin{document}

\psset{unit=1}
\psset{viewpoint=30 7 6}
\psset{action=draw*,incolor=green!20!white, fillcolor=green!20!white, linewidth=0.5pt, opacity=1}

\multido{\iB=2+2}{1}{%
  \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+0.5,\iC=0+1}{3}{%
      \ifodd\iC
        \ifnum\iC<\iB
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi
      \else
        \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
      \fi}
    \end{pspicture}%
}

\multido{\iB=2+2}{2}{%
  \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+0.25,\iC=0+1}{5}{%
      \ifodd\iC
        \ifnum\iC<\iB
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi
      \else
        \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
      \fi}
    \end{pspicture}%
}

\multido{\iB=2+2}{4}{%
  \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+0.125,\iC=0+1}{9}{%
      \ifodd\iC
        \ifnum\iC<\iB
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi
      \else
        \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
      \fi}
    \end{pspicture}%
}

\multido{\iB=2+2}{8}{%
  \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+0.0625,\iC=0+1}{17}{%
      \ifodd\iC
        \ifnum\iC<\iB
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi
      \else
        \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
      \fi}
    \end{pspicture}%
}

\end{document}

现在我想把这四个放到multido另一个中multido：

\documentclass[pstricks, border=0pt]{standalone}
\usepackage{pst-solides3d}

\begin{document}
\psset{unit=1}
\psset{viewpoint=30 7 6}
\psset{action=draw*,incolor=green!20!white, fillcolor=green!20!white, linewidth=0.5pt, opacity=1}

\multido{\iA=1+1}{4}{
 \multido{\iB=2+2}{2^(\iA-1)}{%
  \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+2^(-\iA),\iC=0+1}{2^(\iA)+1}{%
      \ifodd\iC
        \ifnum\iC<\iB
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi
      \else
        \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
      \fi}
    \end{pspicture}%
 }
}
\end{document}

我怎样才能让乳胶计算2^(\iA-1)，2^(-\iA)以及2^(\iA)+1？

Answer 1

\documentclass[pstricks, border=0pt]{standalone}
\usepackage{pst-solides3d}

\begin{document}
\psset{viewpoint=30 7 6, action=draw*,incolor=green!20!white, 
       fillcolor=green!20!white, 
       linewidth=0.5pt,  opacity=1}
\newcount\cntA  \cntA=1 
\newcount\cntB  \cntB=2
\pstFPdiv\rcntB{1}{\the\cntB}

\multido{\iA=1+1}{4}{%
  \multido{\iB=2+2}{\the\cntA}{%
    \begin{pspicture}(-0.8,-0.8)(2,2)
    \multido{\r=0.0+\rcntB,\iC=0+1}{\numexpr\the\cntB+1\relax}{%
        \ifodd\iC
          \ifnum\iC<\iB
            \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
          \fi
        \else
          \psSolid[object=plan,definition=equation, args={[0 0 1 -\r]},base=0 1 0 1]
        \fi}
    \end{pspicture}%
  }%
  \multiply\cntA by 2
  \multiply\cntB by 2
  \pstFPdiv\rcntB{1}{\the\cntB}
}
\end{document}