PSTricks - CTAN

3.2. New optionalarguments 6
1 \begin{pspicture}(-5,-3)(5,3)
2 \psplot[variableLW,startLW=1pt,endLW=20pt,
3 linecolor=magenta!60,variableColor,
4 algebraic,plotpoints=3000,startWL=500,
5 endWL=700]{-5}{5}{2*sin(2*x)+cos(x)}
6 \end{pspicture}
1 \begin{pspicture}(-2.5,-2.5)(2.5,2.5)
2 \pscurve[variableLW,startLW=1pt,endLW=20pt,
3 variableColor](-1,0.5)(-2,1)(2,2)(-1,-2)(2,-2)
4 \end{pspicture}
1 \begin{pspicture}(-2.5,-2.5)(2.5,2.5)
2 \pscurve[variableLW,startLW=1pt,endLW=20pt]%
3 (-1,0.5)(-2,1)(2,2)(-1,-2)(2,-2)
4 \end{pspicture}