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-rw-r--r--Master/texmf-dist/doc/generic/pst-func/pst-func-doc.tex70
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diff --git a/Master/texmf-dist/doc/generic/pst-func/pst-func-doc.tex b/Master/texmf-dist/doc/generic/pst-func/pst-func-doc.tex
index 880c2649723..d08f8bedaad 100644
--- a/Master/texmf-dist/doc/generic/pst-func/pst-func-doc.tex
+++ b/Master/texmf-dist/doc/generic/pst-func/pst-func-doc.tex
@@ -1,4 +1,4 @@
-%% $Id: pst-func-doc.tex 273 2010-01-26 18:28:55Z herbert $
+%% $Id: pst-func-doc.tex 285 2010-02-11 09:40:27Z herbert $
\documentclass[11pt,english,BCOR10mm,DIV12,bibliography=totoc,parskip=false,
smallheadings, headexclude,footexclude,oneside]{pst-doc}
\usepackage[utf8]{inputenc}
@@ -1403,6 +1403,74 @@ and has the syntax (with a default setting of $s=1$ and $\mu=1$):
\clearpage
+\subsection{Weibull distribution}
+
+In probability theory and statistics, the Weibull distribution is a continuous probability
+distribution. The probability density function of a
+Weibull random variable $x$ is:
+
+\begin{align}
+P(x) &= \alpha\beta^{-\alpha} x^{\alpha-1} e^{-\left(\frac{x}{\beta}\right)^\alpha}\\
+D(x) &= 1-e^{-\left(\frac{x}{\beta}\right)^\alpha}
+\end{align}
+
+or slightly different as
+
+\begin{align}
+P(x) &= \frac{\alpha}{\beta}\,x^{\alpha-1} e^{-\frac{x^\alpha}{\beta}}\\
+D(x) &= 1 - e^{-\frac{x^\alpha}{\beta}}
+\end{align}
+
+always for $x\in[0;\infty)$.
+where $\alpha > 0$ is the shape parameter and $\beta > 0$ is the scale parameter of the distribution.
+
+$D(x)$ is the cumulative distribution function of the Weibull distribution. The values for
+$\alpha$ and $\beta$ are preset to 1, but can be changed in the usual way.
+
+The Weibull distribution is related to a number of other probability distributions; in
+particular, it interpolates between the exponential distribution $(\alpha = 1)$ and the
+Rayleigh distribution $(\alpha = 2)$.
+
+\begin{center}
+\psset{unit=2}
+\begin{pspicture*}(-0.5,-0.5)(2.6,2.6)
+\psaxes{->}(0,0)(2.5,2.5)[$x$,-90][$y$,180]
+\multido{\rAlpha=0.5+0.5}{5}{%
+ \psWeibull[alpha=\rAlpha]{0}{2.5}
+ \psWeibullI[alpha=\rAlpha,linestyle=dashed]{0}{2.4}}
+\end{pspicture*}
+%
+\begin{pspicture*}(-0.5,-0.5)(2.6,2.6)
+\psaxes{->}(0,0)(2.5,2.5)[$x$,-90][$y$,180]
+\multido{\rAlpha=0.5+0.5,\rBeta=0.2+0.2}{5}{%
+ \psWeibull[alpha=\rAlpha,beta=\rBeta]{0}{2.5}
+ \psWeibullI[alpha=\rAlpha,beta=\rBeta,linestyle=dashed]{0}{2.4}}
+\end{pspicture*}
+\end{center}
+
+\begin{lstlisting}
+\psset{unit=2}
+\begin{pspicture*}(-0.5,-0.5)(2.6,2.6)
+\psaxes{->}(0,0)(2.5,2.5)[$x$,-90][$y$,180]
+\multido{\rAlpha=0.5+0.5}{5}{%
+ \psWeibull[alpha=\rAlpha]{0}{2.5}
+ \psWeibullI[alpha=\rAlpha,linestyle=dashed]{0}{2.4}}
+\end{pspicture*}
+%
+\begin{pspicture*}(-0.5,-0.5)(2.6,2.6)
+\psaxes{->}(0,0)(2.5,2.5)[$x$,-90][$y$,180]
+\multido{\rAlpha=0.5+0.5,\rBeta=0.2+0.2}{5}{%
+ \psWeibull[alpha=\rAlpha,beta=\rBeta]{0}{2.5}
+ \psWeibullI[alpha=\rAlpha,beta=\rBeta,linestyle=dashed]{0}{2.4}}
+\end{pspicture*}
+\end{lstlisting}
+\psset{unit=1cm}
+
+The starting value for $x$ should always be 0 or greater, if it is
+less than 0 then the macro draws a line from (\#1,0) to (0,0) and
+starts \Lcs{psWeinbull} with 0.
+
+\clearpage
\section{The Lorenz curve}
The so-called \Index{Lorenz curve} is used in economics to describe inequality in