いつもお世話になっています。

対数関数のグラフを描こうと思ったのですが，自然対数しかかけません。
\documentclass{jarticle}
\usepackage{emathPp}

\begin{document}
\begin{zahyou}[ul=10mm](-.5,8)(-3,3)
        \def\Fx{log(X)}
        \YGurafu*[hidarix=0]\Fx
        \Put\migiT[e]{$y=\log{x}$}
\end{zahyou}
\end{document}

は無事かけますが，これを\def\Fx{log2(2,X)}にすると以下のようなエラーが出ます。

This is GUI-Shell Version 1.39.1, Copyright(C) 1996-2000 by Yoshiki OTOBE.
All rights reserved.
GUI-Shell Message(command): platex.exe --src-specials=math,par a.tex

This is pTeXk, Version 3.141592-p3.1.9 (sjis) (Web2C 7.5.5)
 \write18 enabled.
 Source specials enabled.
(./a.tex
pLaTeX2e <2006/01/04>+0 (based on LaTeX2e <2003/12/01> patch level 0)
Babel <v3.8h> and hyphenation patterns for english, usenglishmax, ukenglish, ba
sque, bulgarian, coptic, welsh, czech, slovak, german, ngerman, danish, spanish
, catalan, estonian, finnish, french, irish, polygreek, monogreek, ancientgreek
, croatian, hungarian, interlingua, ibycus, bahasa, icelandic, italian, latin, 
mongolian, dutch, norsk, polish, portuguese, pinyin, romanian, russian, samin, 
slovene, usorbian, serbian, swedish, turkish, ukrainian, dumylang, nohyphenatio
n, loaded.
(c:/usr/local/share/texmf/ptex/platex/base/jarticle.cls
Document Class: jarticle 2002/04/09 v1.4 Standard pLaTeX class
(c:/usr/local/share/texmf/ptex/platex/base/jsize10.clo))
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathPp.sty
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathPh.sty
(c:/usr/local/share/texmf/ptex/platex/misk/emath/epic.sty
Enhancements to Picture Environment. Version 1.2 - Released June 1, 1986
) (c:/usr/local/share/texmf/ptex/platex/misk/emath/eepic.sty
Extension to Epic and LaTeX. Version 1.1e - Released Dec 21, 1999
) (c:/usr/local/share/texmf/ptex/platex/misk/emath/eclarith.sty
eclarith.sty 1.1 --- July 1, 1992
) (c:/usr/local/share/texmf/ptex/platex/misk/emath/emath.sty
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emath2e.sty
(c:/usr/local/share/texmf/tex/latex/amslatex/amsmath.sty
For additional information on amsmath, use the `?' option.
(c:/usr/local/share/texmf/tex/latex/amslatex/amstext.sty
(c:/usr/local/share/texmf/tex/latex/amslatex/amsgen.sty))
(c:/usr/local/share/texmf/tex/latex/amslatex/amsbsy.sty)
(c:/usr/local/share/texmf/tex/latex/amslatex/amsopn.sty))
(c:/usr/local/share/texmf/tex/latex/amsfonts/amssymb.sty
(c:/usr/local/share/texmf/tex/latex/amsfonts/amsfonts.sty))
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathE.sty
(c:/usr/local/share/texmf/tex/latex/tools/enumerate.sty)
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathEc.sty
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathC.sty
(c:/usr/local/share/texmf/tex/latex/tools/calc.sty)
(c:/usr/local/share/texmf/tex/latex/base/ifthen.sty))
(c:/usr/local/share/texmf/tex/latex/graphics/keyval.sty))
(c:/usr/local/share/texmf/ptex/platex/misk/emath/jquote.sty)
(c:/usr/local/share/texmf/ptex/platex/misk/emath/emathK.sty))))
(c:/usr/local/share/texmf/tex/latex/graphics/graphicx.sty
(c:/usr/local/share/texmf/tex/latex/graphics/graphics.sty
(c:/usr/local/share/texmf/tex/latex/graphics/trig.sty)
(c:/usr/local/share/texmf/tex/latex/config/graphics.cfg)
(c:/usr/local/share/texmf/tex/latex/graphics/dvips.def)))
(c:/usr/local/share/texmf/tex/latex/graphics/color.sty
(c:/usr/local/share/texmf/tex/latex/config/color.cfg)
(c:/usr/local/share/texmf/tex/latex/graphics/dvipsnam.def)))) (./a.aux)Can't take log of 0 at C:/Perl/lib/emath.pl line 17.

Runaway argument?
! Paragraph ended before \@trimleading was complete.
<to be read again> 
                   \par 
l.7         \YGurafu*[hidarix=0]\Fx
                                   
? 

解決済みのものであれば申し訳ないのですが，どなたかよろしくお願いします。

▼関連発言
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└◆5267:log2(2,X)のグラフがエラーします。 [gaku] 10/05 17:01
　├◆5268:Re:log2(2,X)のグラフがエラーします。 [田中徹] 10/05 17:16
　│└◆5269:Re[2]:log2(2,X)のグラフがエラーします。 [gaku] 10/05 17:35
　└◆5270:Re:log2(2,X)のグラフがエラーします。 [tDB] 10/05 17:38
　　└◆5271:Re[2]:log2(2,X)のグラフがエラーします。 [gaku] 10/05 17:41<-last