什么原因导致此错误？

Question

看到 Herbert 的回答后，显然如果我意识到以下代码的第一行应该是，则不应该出现此问题\documentclass{beamer}。问题通常来自于不知道自己在做什么。

请关闭这个过于本地化的问题。

---

抱歉，标题不好！

\documentclass{article}
\usepackage{filecontents}
\begin{filecontents*}{pst-sex.sty}
% ========================================================
% Copyright (c) 2013 Bugbusters. All rights reservered.
% LPPL LaTeX Public Project License
% ========================================================
\NeedsTeXFormat{LaTeX2e}[1994/06/01] 
\ProvidesPackage{pst-sex}[2013/04/23 v3.141592654 Constant declator for StackEXchange]
\RequirePackage[nomessages]{fp}
\RequirePackage{pstricks}

% removing a trailing space in the original fp.sty
\def\FP@pow#1#2#3{%
    % #1 macro, which gets the result
    % #2 base
    % #3 exponent
    %
    \FP@beginmessage{POW}%
    %
    {\def\FP@beginmessage##1{}%
     \def\FP@endmessage##1{}%
     %
     \FPifzero{#2}%
        \FP@pow@zero{#3}%
     \else%
        \FPln\FP@tmpd{#2}%
        \FPmul\FP@tmpd\FP@tmpd{#3}%
        \FPexp\FP@tmp\FP@tmpd%
     \fi%
     %
     \global\let\FP@tmp\FP@tmp%
    }%
    %
    \FP@endmessage{}%
    %
    \let#1\FP@tmp%
}

% constants declarator
\def\LoadConstants{}
\newcommand\const[3][]{%
    \if\relax\detokenize{#1}\relax
        \edef\pst@@sex@@temporary{#3}%
    \else
        \edef\pst@@sex@@temporary{round(#3:#1)}%
    \fi
    \expandafter\FPeval\csname#2\expandafter\endcsname
        \expandafter{\expandafter{\pst@@sex@@temporary}}%
    \toks0=\expandafter{\LoadConstants\pstVerb}
    \edef\LoadConstants{\the\toks0 {/#2 \csname#2\endcsname\space def}}}

% inject \LoadConstants into pspicture
\def\pst@@picture@i[#1]#2(#3,#4){%
    \renewcommand\const[3][]{%
    \if\relax\detokenize{##1}\relax
        \edef\pst@@sex@@temporary{##3}%
    \else
        \edef\pst@@sex@@temporary{round(##3:##1)}%
    \fi
    \expandafter\FPeval\csname##2\expandafter\endcsname
        \expandafter{\expandafter{\pst@@sex@@temporary}}%
        \pstVerb{/##2 \csname##2\endcsname\space def}\ignorespaces}%
    \@ifnextchar(% ignore anything between [] and ()
    {\pst@@@picture[#1](#3,#4)\LoadConstants}%
    {\pst@@@picture[#1](0,0)(#3,#4)\LoadConstants}}

\endinput
% pst-sex.sty
\end{filecontents*}


\usepackage{multido}
\usepackage{pst-sex}
\usepackage[tightpage]{preview}
\PreviewEnvironment{pspicture}
\PreviewBorder=25pt\relax


\SpecialCoor
\const{Side}{root(2,17)}% the square root of 17

\begin{document}
\begin{frame}   
\begin{pspicture}(\Side,\Side)
    \psframe(!Side dup)\pause
    \multido{\i=0+30}{12}{%
        \const[7]{temp}{cos(\i*pi/180)}
        \rput{\i}(!Side 2 div dup 2 copy temp mul add 3 1 roll \i\space sin mul add){$\temp$}\pause
    }
\end{pspicture}
\end{frame}
\end{document}

什么原因导致此错误？

Answer 1

选择正确的文档类别也许是一个好主意;-)

\documentclass{article}
[ ... ]

但您正在使用frame环境......

pstricks.tex然而，随着http://texnik.dante.de/tex/generic/pstricks/我可以做类似的事情：

\documentclass{beamer}
\usepackage{pst-tools,multido}
\SpecialCoor

\begin{document}
\begin{frame}{title}   
\begin{pspicture}(-4.5,-4.5)(4.5,4.5)
 \psframe(+{-sqrt(17)/2}, x)(+{sqrt(17)/2}, x)\pause
 \multido{\iA=0+30}{12}{\rput{\iA}(1;\iA){\psPrintValue[algebraic]{\iA, cos(x*Pi/180)}}\pause}
\end{pspicture}
\end{frame}
\end{document}