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<div>Please take a look at the following code: evidence of bugs or brain damage? Troubled lines</div>
<div>prefixed with %-> below. Using MikTeX 2.4 and dvips.</div>
<div> </div>
<div>%% lensbug.tex</div>
<div>\listfiles<br>
\documentclass{article}<br>
\usepackage{pstricks}<br>
\usepackage{pst-plot}<br>
\usepackage{pst-lens}<br>
\usepackage{pst-fill}</div>
<div> </div>
<div>\newcommand{\f}{\mathrm f{}}<br>
\renewcommand{\d}[1]{\mathop{\mathrm d#1}\nolimits}</div>
<div>\newgray{mygray}{0.9}</div>
<div> </div>
<div>\begin{document}</div>
<div> </div>
<div>\def\incircle{% my boxfill, loads of dots<br>
\pspicture(0,0)(0.2,0.2)\psdots(0.1,0.1)\endpspicture<br>
}</div>
<div> </div>
<div>\def\inpic{% my lens picture<br>
\rput(1.9,0.1){<br>
\begin{pspicture}(-1,-1)(1,1)<br>
\psboxfill{\incircle}</div>
<div><br>
%% begin problem<br>
%% first problem:</div>
<div>%% remove %-> and feel the heat<br>
%-> \psframe[fillstyle=boxfill](-1,0)(1,1)<br>
%% end problem</div>
<div><br>
\psframe[fillstyle=crosshatch,hatchsep=1pt](-0.3,0)(0.4,1)% **</div>
<div><br>
%% begin problem</div>
<div>%% second problem:<br>
%% an alternative to the crosshatch style ** above<br>
%% the fill bleeds into the lens surround, and looks awful<br>
%-> \psframe[fillstyle=solid,fillcolor=mygray](-0.3,0)(0.4,1)<br>
%% end problem</div>
<div><br>
\psline(-1,0)(1,0)<br>
\psline(-0.3,0)(-0.3,1)<br>
\psline(0.4,0)(0.4,1)<br>
\uput[d](-0.3,0){$\mathstrut x$}<br>
\uput[d](0.4,0){$\mathstrut x+\d x$}<br>
\end{pspicture}<br>
}<br>
}</div>
<div> </div>
<div>\psset{unit=1.75cm}<br>
\begin{pspicture}(-.5,-.5)(5,3) % the plot thickens<br>
\psclip{% shaded area in plot<br>
\pscustom[linestyle=none]{%<br>
\pscurve(0,1.8)(0.5,2.3)(2,2.7)(3,2.4)(4.5,1.6)(5,1.5)<br>
\lineto(5,0)<br>
\lineto(0,0)<br>
}<br>
}<br>
\psframe*[linecolor=mygray](0.5,0)(4.5,3)<br>
\endpsclip<br>
\psaxes[labels=none,ticks=none]{->}(0,0)(-.2,-.2)(5,3)<br>
\pscurve(0,1.8)(0.5,2.3)(2,2.7)(3,2.4)(4.5,1.6)(5,1.5)<br>
\uput[r](5,1.5){$y=\f(x)$}<br>
\psline(2,0)(2,2.7)<br>
\uput[d](2,0){$\d x$}<br>
\psdots(2,2.7)<br>
\uput[ur](2,2.7){$(x,y)$}<br>
\uput[d](0.5,0){$a$}<br>
\uput[d](4.5,0){$b$}<br>
\uput[r](5,0){$x$}<br>
\uput[l](0,3){$y$}<br>
\PstLens[LensSize=.75,LensRotation=75](2,0.01){\inpic} % doing it<br>
\end{pspicture}</div>
<div> </div>
<div>\end{document}</div>
<div> </div>
<div> *File List*<br>
article.cls 2005/09/16 v1.4f Standard LaTeX document class<br>
size10.clo 2005/09/16 v1.4f Standard LaTeX file (size option)<br>
pstricks.sty 2005/12/19 v0.31 LaTeX wrapper for `PSTricks'(RN,HV)<br>
pstricks.tex 2006/02/06 v1.14a `PSTricks' (tvz)<br>
xcolor.sty 2005/12/21 v2.09 LaTeX color extensions (UK)<br>
color.cfg 2005/12/29 v1.1 MiKTeX 'color' configuration<br>
dvips.def 1999/02/16 v3.0i Driver-dependant file (DPC,SPQR)<br>
pst-plot.sty 2004/07/15 package wrapper for pst-plot.tex<br>
pst-plot.tex 2004/05/18 1.41 `pst-plot' (tvz)<br>
pst-lens.sty 2005/09/02 package wrapper for pst-lens.tex (hv)<br>
pst-lens.tex 2006/06/06 v1.02 `PST-lens' (hv)<br>
pst-xkey.tex 2005/11/25 v1.6 PSTricks specialization of xkeyval (HA)<br>
xkeyval.sty 2005/11/25 v2.5e package option processing (HA)<br>
xkeyval.tex 2005/11/25 v2.5e key=value parser (HA)<br>
pst-fill.sty 2004/07/15 package wrapper for pst-fill.tex<br>
pst-fill.tex 2004/08/18 97 patch 4 `pst-fill' (tvz)<br>
***********<br>
</div>
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