%===============================axoman.tex=============================%
%\documentstyle[11pt,a4,axodraw]{article}
\documentclass[11pt,a4paper]{article}
\RequirePackage{axodraw}

\def\KeyWord#1{$\backslash$\IfColor{$\!\!$\textRed{#1}\textBlack}{#1}$\!\!$}

\begin{document}

\begin{center}
{\Huge \IfColor{\textRed{A}\textOrange{X}\textYellow{O}\textGreen
{D}\textBlue{R}\textRoyalPurple{A}\textViolet{W}\textBlack$\!\!\!$}{AXODRAW}} \\
\vspace{3cm}
{\LARGE  J.A.M.Vermaseren} \\
\vspace{4mm}
NIKHEF-H \\ P.O. Box 41882 \\ 1009 DB Amsterdam \\ \vspace{5mm}
\end{center}

\vspace{5cm}

\begin{abstract}
Axodraw is a set of drawing primitives for use in \LaTeX. These can be used
for the drawing of Feynman diagrams, flow charts and simple graphics.
Because it uses postscript for its drawing commands it works only in
combination with the dvips of Radical Eye Software which is presently the
most popular dvips program. More will be added in the future. It allows
whole articles including their pictures to be contained in a single file,
thereby making it easier to exchange the article file by e-mail. The
current version\footnote{An earlier version of Axodraw was published
in Comp. Phys. Comm. 83 (1994) 45.} supports color according to the scheme
implemented in the file colordvi.sty which comes with most \TeX{}
distributions.
\end{abstract}

\newpage

\section{Using Axodraw}

The file axodraw.sty is a style file for \LaTeX{}. It should be included
in the documentstyle statement at the beginning of the
document. An example would be: \IfColor{\textBlue}{}
\begin{verbatim}
    \documentstyle[a4,11pt,axodraw]{article}
\end{verbatim}
\IfColor{\textBlack}{}
Because axodraw.sty reads also the epsf.sty file that comes with many
implementations of \TeX{} and in particular those that rely on the dvips
program by Radical Eye Software for the printing, this file should be
present in the system. If this file is not available one should obtain it
from another system. The file colordvi.sty is also read, but if it is not
present there will be no error. The user should just not use color in that
case. The author feels in no way responsible for the problems that may
occur when a different dvi-to-postscript program is used.

The drawing is actually done in postscript. Because the above mentioned
dvi-to-postscript converter allows the inclusion of postscript code the
graphics primitives have been included in the file axodraw.sty in terms
of postscript. If another postscript converter is used, one may have to
adapt the syntax of the inclusion of this code to the local system.

The commands of Axodraw should be executed inside either the picture or the
figure environment. Inside this environment it is possible to place objects
at arbitrary positions and put text between them. In principle one could
try to draw objects with the facilities of \LaTeX{} itself, but it turns
out that the commands in the picture environment are not very powerful.
Axodraw gives good extensions of them. An example would be
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center} \begin{picture}(300,100)(0,0)
    \SetColor{Red}
    \GlueArc(150,50)(40,0,180){5}{8}
    \SetColor{Green}
    \GlueArc(150,50)(40,180,360){5}{8}
    \SetColor{Blue}
    \Gluon(50,50)(110,50){5}{4}  \Vertex(110,50){2}
    \Gluon(190,50)(250,50){5}{4} \Vertex(190,50){2}
    \end{picture}  \\ {\sl A gluon loop diagram} \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
This code would result in:
\begin{center} \begin{picture}(300,100)(0,0)
\SetColor{Red}
\GlueArc(150,50)(40,0,180){5}{8}
\SetColor{Green}
\GlueArc(150,50)(40,180,360){5}{8}
\SetColor{Blue}
\Gluon(50,50)(110,50){5}{4}  \Vertex(110,50){2}
\Gluon(190,50)(250,50){5}{4} \Vertex(190,50){2}
\end{picture}  \\ {\sl A gluon loop diagram} \end{center}
The syntax and the meaning of these command are explained in the next
section. One should note that all coordinates are presented in units of
1 point. There are 72 points in an inch. It is possible to use scale
transformations if these units are not convenient.

Currently the primitives are mainly useful for the drawing of Feynman
diagrams and the drawing of flowcharts. This means that the commands were
designed to draw a number of these graphs. Of course many more things can
be drawn with them, like scatter plots, histograms etc.

The current manual uses only those color commands that are safe on systems
that do not have the required colordvi.sty file. It should however be clear
from the examples how to use the other features. To allow the creation of
complicated color commands that will work also in the absence of the
colordvi.sty file there is a macro IfColor which is described below with
the other commands.

\section{The commands}

The commands that are currently available in Axodraw are (in alphabetic
order):
\begin{itemize}
\item \KeyWord{ArrowArc}(x,y)(r,$\phi_1$,$\phi_2$) \hfill \\
    Draws an arc segment centered around (x,y). The radius is r. The
    arc-segment runs counterclockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. In the middle of the segment there will
    be an arrow.
\item \KeyWord{ArrowArcn}(x,y)(radius,$\phi_1$,$\phi_2$) \hfill \\
    Draws an arc segment centered around (x,y). The radius is r. The
    arc-segment runs clockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. In the middle of the segment there will
    be an arrow.
\item \KeyWord{ArrowLine}($x_1$,$y_1$)($x_2$,$y_2$) \hfill \\
    Draws a line from ($x_1$,$y_1$) to ($x_2$,$y_2$). There will be an
    arrow in the middle of the line.
\item \KeyWord{BBox}($x_1$,$y_1$)($x_2$,$y_2$) \hfill \\
    Draws a box of which the contents are blanked out. This means that
    anything that was present at the position of the box will be
    overwritten. The lower left corner of the box is at ($x_1$,$y_1$) and
    ($x_2$,$y_2$) is the upper right corner of the box.
\item \KeyWord{BBoxc}(x,y)(width,height) \hfill \\
    Draws a box of which the contents are blanked out. This means that
    anything that was present at the position of the box will be
    overwritten. The center of the box is at (x,y). Width and height refer
    to the full width and the full height of the box.
\item \KeyWord{BCirc}(x,y)\{r\} \hfill \\
    Draws a circle of which the contents are blanked out. This means that
    anything that was present at the position of the circle will be
    overwritten. The center of the circle is at (x,y). r is its radius.
\item \KeyWord{Boxc}(x,y)(width,height) \hfill \\
    Draws a box. The center of the box is at (x,y). Width and height refer
    to the full width and the full height of the box.
\item \KeyWord{BText}(x,y)\{text\} \hfill \\
    Draws a box with one line of centered postscript text in it. The box is
    just big enough to fit around the text. The coordinates refer to the
    center of the box. The box is like a BBox in that it blanks out
    whatever was at the position of the box.
\item \KeyWord{B2Text}(x,y)\{text1\}\{text2\} \hfill \\
    Draws a box with two lines of centered postscript text in it. The box is
    just big enough to fit around the text. The coordinates refer to the
    center of the box. The box is like a BBox in that it blanks out
    whatever was at the position of the box.
\item \KeyWord{CArc}(x,y)(radius,$\phi_1$,$\phi_2$) \hfill \\
    Draws an arc segment centered around (x,y). The radius is r. The
    arc-segment runs counterclockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees.
\item \KeyWord{CBox}($x_1$,$y_1$)($x_2$,$y_2$)\{color1\}\{color2\} \hfill \\
    Draws a box. The lower left corner of the box is at ($x_1$,$y_1$) and
    ($x_2$,$y_2$) is the upper right corner of the box. The contents of
    the box are lost. The color of the box will be color1 and the color of
    the background inside the box will be color2.
\item \KeyWord{CBoxc}(x,y)(width,height)\{color1\}\{color2\} \hfill \\
    Draws a box of which the contents are blanked out. This means that
    anything that was present at the position of the box will be
    overwritten. The center of the box is at (x,y). Width and height refer
    to the full width and the full height of the box. The color of the box
    will be color1 and the color of the background inside the box will be
    color2.
\item \KeyWord{CCirc}(x,y)\{radius\}\{color1\}\{color2\} \hfill \\
    Draws a circle around (x,y) with radius r. The contents of
    the circle are lost. The color of the box will be color1 and the color
    of the background inside the box will be color2.
\item \KeyWord{COval}(x,y)(h,w)($\phi$)\{color1\}\{color2\} \hfill \\
    Draws an oval with an internal color indicated by color2. The oval
    itself has the color color1. The center of the oval
    is given by (x,y). Its height is h, and the width is w. In addition
    the oval can be rotated counterclockwise over $\phi$ degrees. The
    oval overwrites anything that used to be in its position.
\item \KeyWord{CText}(x,y)\{color1\}\{color2\}\{text\} \hfill \\
    Draws a box with one line of centered postscript text in it. The
    box is just big enough to fit around the text. The coordinates refer to
    the center of the box. The box is like a CBox in that it blanks out
    whatever was at the position of the box. The color of the box and the
    text inside is color1 and the background inside has the color color2.
\item \KeyWord{C2Text}(x,y)\{color1\}\{color2\}\{text1\}\{text2\} \hfill \\
    Draws a box with two lines of centered postscript text in it.
    The box is just big enough to fit around the text. The coordinates
    refer to the center of the box. The box is like a CBox in that it blanks
    out whatever was at the position of the box. The color of the box and the
    text inside is color1 and the background inside has the color color2.
\item \KeyWord{Curve}\{$(x_1,y_1)(x_2,y_2)\cdots(x_n,y_n)$\} \hfill \\
    Draws a curve through the given points. The x-values are supposed to
    be in ascending order. The curve is a combination of quadratic and
    third order segments and is continuous in its first and second derivatives.
\item \KeyWord{DashArrowArc}(x,y)(r,$\phi_1$,$\phi_2$)\{dashsize\} \hfill \\
    Draws a dashed arc segment centered around (x,y). The radius is r. The
    arc-segment runs counterclockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. In the middle of the segment there will
    be an arrow. The size of the dashes is approximately equal to
    `dashsize'.
\item \KeyWord{DashArrowArcn}(x,y)(radius,$\phi_1$,$\phi_2$)\{dashsize\} \hfill \\
    Draws a dashed arc segment centered around (x,y). The radius is r. The
    arc-segment runs clockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. In the middle of the segment there will
    be an arrow. The size of the dashes is approximately equal to
    `dashsize'.
\item \KeyWord{DashArrowLine}($x_1$,$y_1$)($x_2$,$y_2$)\{dashsize\} \hfill \\
    Draws a line from ($x_1$,$y_1$) to ($x_2$,$y_2$) with a dashed
    pattern. The size of the black parts of the pattern is given by
    `dashsize'. The alternating pieces have equal length. The size of
    the pattern is adjusted so that both the begin and the end are
    black. Halfway the line there is an arrow.
\item \KeyWord{DashCArc}(x,y)(radius,$\phi_1$,$\phi_2$)\{dashsize\} \hfill \\
    Draws a dashed arc segment centered around (x,y). The radius is r. The
    arc-segment runs counterclockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. The size of the dashes is determined by
    `dashsize'. This size is adjusted somewhat to make the result look
    nice.
\item \KeyWord{DashCurve}\{$(x_1,y_1)(x_2,y_2)\cdots(x_n,y_n)$\}\{
    dashsize\} \hfill \\
    Draws a dashed curve through the given points. The x-values are
    supposed to be in ascending order. The curve is a combination of
    quadratic and third order segments. The size of the black parts and
    the white parts will be approximately `dashsize' each. Some
    adjustment takes place to make the pattern come out right at the
    endpoints.
\item \KeyWord{DashLine}($x_1$,$y_1$)($x_2$,$y_2$)\{dashsize\} \hfill \\
    Draws a line from ($x_1$,$y_1$) to ($x_2$,$y_2$) with a dashed
    pattern. The size of the black parts of the pattern is given by
    `dashsize'. The alternating pieces have equal length. The size of
    the pattern is adjusted so that both the begin and the end are
    black.
\item \KeyWord{EBox}($x_1$,$y_1$)($x_2$,$y_2$) \hfill \\
    Draws a box. The lower left corner of the box is at ($x_1$,$y_1$) and
    ($x_2$,$y_2$) is the upper right corner of the box.
\item \KeyWord{IfColor}\{arg1\}\{arg2\} \hfill \\
    If the file colordvi.sty is present the first argument will be
    executed. If this file is not present the second argument will be
    executed. For examples, see some of the figures. This command can also
    be used in the regular text of the \LaTeX{} file.
\item \KeyWord{GBox}($x_1$,$y_1$)($x_2$,$y_2$)\{grayscale\} \hfill \\
    Draws a box. The lower left corner of the box is at ($x_1$,$y_1$) and
    ($x_2$,$y_2$) is the upper right corner of the box. The contents of
    the box are lost. They are overwritten with a color gray that is
    indicated by the parameter `grayscale'. This parameter can have
    values ranging from 0 (black) to 1 (white).
\item \KeyWord{GBoxc}(x,y)(width,height)\{grayscale\} \hfill \\
    Draws a box. The center of the box is at (x,y). Width and height refer
    to the full width and the full height of the box. The contents of
    the box are lost. They are overwritten with a color gray that is
    indicated by the parameter `grayscale'. This parameter can have
    values ranging from 0 (black) to 1 (white).
\item \KeyWord{GCirc}(x,y)\{radius\}\{grayscale\} \hfill \\
    Draws a circle around (x,y) with radius r. The contents of
    the circle are lost. They are overwritten with a color gray that is
    indicated by the parameter `grayscale'. This parameter can have
    values ranging from 0 (black) to 1 (white).
\item \KeyWord{GlueArc}(x,y)(r,$\phi_1$,$\phi_2$)\{amplitude\}\{windings\} \hfill \\
    Draws a gluon on an arc-segment. The center of the arc is (x,y) and r
    is its radius. The arc segment runs counterclockwise from $\phi_1$
    to $\phi_2$. The width of the gluon is twice `amplitude', and the
    number of windings is given by the last parameter. Note that whether
    the curls are inside or outside can be influenced with the sign of
    the amplitude. When it is positive the curls are on the inside.
\item \KeyWord{Gluon}($x_1$,$y_1$)($x_2$,$y_2$)\{amplitude\}\{windings\} \hfill \\
    Draws a gluon from ($x_1$,$y_1$) to ($x_2$,$y_2$). The width of the
    gluon will be twice the value of `amplitude'. The number of windings
    is given by the last parameter. If this parameter is not an integer
    it will be rounded to an integer value. The side at which the
    windings lie is determined by the order of the two coordinates. Also
    a negative amplitude can change this side.
\item \KeyWord{GOval}(x,y)(h,w)($\phi$)\{grayscale\} Draws an oval with
    an internal color indicated by grayscale. This parameter can have
    values ranging from 0 (black) to 1 (white). The center of the oval
    is given by (x,y). Its height is h, and the width is w. In addition
    the oval can be rotated counterclockwise over $\phi$ degrees. The
    oval overwrites anything that used to be in its position.
\item \KeyWord{GText}(x,y)\{grayscale\}\{text\} \hfill \\
    Draws a gray box with one line of centered postscript text in it. The
    box is just big enough to fit around the text. The coordinates refer to
    the center of the box. The box is like a BBox in that it blanks out
    whatever was at the position of the box.
\item \KeyWord{G2Text}(x,y)\{grayscale\}\{text1\}\{text2\} \hfill \\
    Draws a gray box with two lines of centered postscript text in it.
    The box is just big enough to fit around the text. The coordinates
    refer to the center of the box. The box is like a BBox in that it
    blanks out whatever was at the position of the box.
\item \KeyWord{LinAxis}($x_1$,$y_1$)($x_2$,$y_2$)($N_D$,$d$,hashsize
    ,offset,width) \hfill \\
    This draws a line to be used as an axis in a graph. Along the axis
    are hash marks. Going from the first coordinate to the second, the
    hash marks are on the left side if `hashsize', which is the size of the
    hash marks, is positive and on the right side if it is negative.
    $N_D$ is the number of `decades', indicated by fat hash marks, and
    $d$ is the number of subdivisions inside each decade. The offset
    parameter tells to which subdivision the first coordinate
    corresponds. When it is zero, this coordinate corresponds to a fat
    mark of a decade. Because axes have their own width, this is
    indicated with the last parameter.
\item \KeyWord{Line}($x_1$,$y_1$)($x_2$,$y_2$) \hfill \\
    Draws a line from ($x_1$,$y_1$) to ($x_2$,$y_2$).
\item \KeyWord{LogAxis}($x_1$,$y_1$)($x_2$,$y_2$)($N_L$,hashsize
    ,offset,width) \hfill \\
    This draws a line to be used as an axis in a graph. Along the axis
    are hash marks. Going from the first coordinate to the second, the
    hash marks are on the left side if `hashsize', which is the size of the
    hash marks, is positive and on the right side if it is negative.
    $N_L$ is the number of orders of magnitude, indicated by fat
    hash marks. The offset parameter tells to which integer subdivision
    the first coordinate corresponds. When it is zero, this coordinate
    corresponds to a fat mark, which is identical to when the value
    would have been 1. Because axes have their own width, this is
    indicated with the last parameter.
\item \KeyWord{LongArrow}($x_1$,$y_1$)($x_2$,$y_2$) \hfill \\
    Draws a line from ($x_1$,$y_1$) to ($x_2$,$y_2$). There will be an
    arrow at the end of the line.
\item \KeyWord{LongArrowArc}(x,y)(r,$\phi_1$,$\phi_2$) \hfill \\
    Draws an arc segment centered around (x,y). The radius is r. The
    arc-segment runs counterclockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. At the end of the segment there will
    be an arrow.
\item \KeyWord{LongArrowArcn}(x,y)(radius,$\phi_1$,$\phi_2$) \hfill \\
    Draws an arc segment centered around (x,y). The radius is r. The
    arc-segment runs clockwise from $\phi_1$ to $\phi_2$. All
    angles are given in degrees. At the end of the segment there will
    be an arrow.
\item \KeyWord{Oval}(x,y)(h,w)($\phi$) Draws an oval.
    The center of the oval
    is given by (x,y). Its height is h, and the width is w. In addition
    the oval can be rotated counterclockwise over $\phi$ degrees. The
    oval does not overwrite its contents.
\item \KeyWord{Photon}($x_1$,$y_1$)($x_2$,$y_2$)\{amplitude\}\{wiggles\} \hfill \\
    Draws a photon from ($x_1$,$y_1$) to ($x_2$,$y_2$). The width of the
    photon will be twice the value of `amplitude'. The number of wiggles
    is given by the last parameter. If twice this parameter is not an integer
    it will be rounded to an integer value. Whether the first wiggle
    starts up or down can be influenced with the sign of the amplitude.
\item \KeyWord{PhotonArc}(x,y)(r,$\phi_1$,$\phi_2$)\{amplitude\}\{wiggles\} \hfill \\
    Draws a photon on an arc-segment. The center of the arc is (x,y) and r
    is its radius. The arc segment runs counterclockwise from $\phi_1$
    to $\phi_2$. The width of the photon is twice `amplitude', and the
    number of wiggles is given by the last parameter. Note that
    the sign of the amplitude influences whether the photon starts going
    outside (positive) or starts going inside (negative). If one likes
    the photon to reach both endpoints from the outside the number of
    wiggles should be an integer plus 0.5.
\item \KeyWord{PText}(x,y)($\phi$)$[$mode$]$\{text\} \hfill \\
    Places a postscript text. The focal point is (x,y). The text is the last
    parameter. The mode parameter tells how the text should be
    positioned with respect to the focal point. If this parameter is
    omitted the center of the text will correspond to the focal point.
    Other options are: l for having the left side correspond to the
    focal point, r for having the right side correspond to it, t for
    having the top at the focal point and b for the bottom. One may
    combine two letters as in $[$bl$]$, as long as it makes sense. The
    parameter $\phi$ is a rotation angle. The text is written in the
    current postscript font. This font can be set with the SetPFont
    command.
\item \KeyWord{rText}(x,y)$[$mode$][$rotation$]$\{text\} \hfill \\
    Places a rotated text. The focal point is (x,y). The text is the last
    parameter. If the rotation parameter is the character l the text
    will be rotated left by 90 degrees, if it is an r it will be rotated
    to the right by 90 degrees and when it is the character u the text
    will be rotated by 180 degrees. When there is no character there is
    no rotation and the command is identical to the Text command.
    The mode parameter tells how the resulting box should be
    positioned with respect to the focal point. If this parameter is
    omitted the center of the box will correspond to the focal point.
    Other options are: l for having the left side correspond to the
    focal point, r for having the right side correspond to it, t for
    having the top at the focal point and b for the bottom. One may
    combine two letters as in $[$bl$]$, as long as it makes sense.
\item \KeyWord{SetColor}\{NameOfColor\} \hfill \\
    Sets the color for the next commands. This command onlt affects the
    current picture. In addition it does not affect the text commands that
    write in \TeX{} mode. Also the commands that draw gray boxes are not
    affected. For influencing the color of the \TeX{} or \LaTeX{} output
    one can use the commands mentioned in the colordvi.sty file.
\item \KeyWord{SetPFont}\{fontname\}\{fontsize\} \hfill \\
    Sets the postscript font to a given type and scale.
\item \KeyWord{SetScale}\{scalevalue\} \hfill \\
    Changes the scale of all graphics operations. Unfortunately it does
    not change the scale of the text operations (yet?). A `scalevalue' of
    1 is the default. It is allowed to use floating point values.
\item \KeyWord{SetOffset}(x\_offset,y\_offset) \hfill \\
    Adds the offset values to all coordinates at the \TeX{} level. This
    makes it easier to move figures around.
\item \KeyWord{SetScaledOffset}(x\_offset,y\_offset) \hfill \\
    Adds the offset values to all coordinates at the postscript level.
    This is done after scaling has been applied. Hence one can work with
    the scaled coordinates. This can be very handy when drawing curves.
\item \KeyWord{SetWidth}\{widthvalue\} \hfill \\
    Changes the linewidth in all graphics operations. It does
    not change the linewidth of the text operations. That is a matter of
    font selection. A `widthvalue' of
    0.5 is the default. It is allowed to use floating point values.
\item \KeyWord{Text}(x,y)$[$mode$]$\{text\} \hfill \\
    Places a text. The focal point is (x,y). The text is the last
    parameter. The mode parameter tells how the text should be
    positioned with respect to the focal point. If this parameter is
    omitted the center of the text will correspond to the focal point.
    Other options are: l for having the left side correspond to the
    focal point, r for having the right side correspond to it, t for
    having the top at the focal point and b for the bottom. One may
    combine two letters as in $[$bl$]$, as long as it makes sense.
\item \KeyWord{Vertex}(x,y)\{r\} \hfill \\
    Draws a fat dot at (x,y). The radius of the dot is given by r.
\item \KeyWord{ZigZag}($x_1$,$y_1$)($x_2$,$y_2$)\{amplitude\}\{wiggles\} \hfill \\
    Draws a zigzag line from ($x_1$,$y_1$) to ($x_2$,$y_2$). The width of the
    zigzagging will be twice the value of `amplitude'. The number of zigzags
    is given by the last parameter. If twice this parameter is not an integer
    it will be rounded to an integer value. Whether the first zigzag
    starts up or down can be influenced with the sign of the amplitude.
\end{itemize}

A note about color. The names of the colors can be found in the local file
colordvi.sty or colordvi.tex. This file gives also the commands that allow
the user to change the color of the text.

\section{Examples}

Although the previous section contains all the commands and their proper
syntax a few examples may be helpful.
\subsection{Text modes}
The meaning of the mode characters in the text commands can best be
demonstrated. The statements
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center}  \begin{picture}(300,100)(0,0)
    \SetColor{BrickRed}
    \CArc(50,75)(2,0,360)  \Text(50,75)[lt]{left-top}
    \CArc(50,50)(2,0,360)  \Text(50,50)[l]{left-center}
    \CArc(50,25)(2,0,360)  \Text(50,25)[lb]{left-bottom}
    \CArc(150,75)(2,0,360) \Text(150,75)[t]{center-top}
    \CArc(150,50)(2,0,360) \Text(150,50)[]{center-center}
    \CArc(150,25)(2,0,360) \Text(150,25)[b]{center-bottom}
    \CArc(250,75)(2,0,360) \Text(250,75)[rt]{right-top}
    \CArc(250,50)(2,0,360) \Text(250,50)[r]{right-center}
    \CArc(250,25)(2,0,360) \Text(250,25)[rb]{right-bottom}
    \end{picture}   \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
produce 9 texts and for each the focal point is indicated by a little
circle. It looks like
\begin{center}
\begin{picture}(300,100)(0,0)
\SetColor{BrickRed}
\CArc(50,75)(2,0,360)  \Text(50,75)[lt]{left-top}
\CArc(50,50)(2,0,360)  \Text(50,50)[l]{left-center}
\CArc(50,25)(2,0,360)  \Text(50,25)[lb]{left-bottom}
\CArc(150,75)(2,0,360) \Text(150,75)[t]{center-top}
\CArc(150,50)(2,0,360) \Text(150,50)[]{center-center}
\CArc(150,25)(2,0,360) \Text(150,25)[b]{center-bottom}
\CArc(250,75)(2,0,360) \Text(250,75)[rt]{right-top}
\CArc(250,50)(2,0,360) \Text(250,50)[r]{right-center}
\CArc(250,25)(2,0,360) \Text(250,25)[rb]{right-bottom}
\end{picture}
\end{center}
This illustrates exactly all the combinations of the mode characters and
what their effects are. The commands $\backslash$Text and
$\backslash$rText give a tex according to \LaTeX{}. This text is
insensitive to the scaling commands, and the color of the text should be
set with the regular color commands given in colordvi.sty. The text in the
$\backslash$PText command (and the various boxes with text) is a postscript
text. Such text is sensitive to the scaling commands and in addition the
color is set with the $\backslash$SetColor command or in the command itself
(in the case of the boxes). In the case of \LaTeX{} text
it can of course contain different fonts,
math mode and all those little things that are usually easier in
\LaTeX{} than in postscript.

\subsection{The windings of a gluon}

Gluons are traditionally represented by a two dimensional projection of
a helix. Actually close inspection of some pretty gluons reveals that
it is usually not quite a helix. Hence the gluons in Axodraw are also
not quite helices. In addition one may notice that the begin and end
points deviate slightly from the regular windings. This makes it more in
agreement with hand drawn gluons. When a gluon is drawn, one needs not
only its begin and end points but there is an amplitude connected to
this almost helix, and in addition there are windings. The number of
windings is the number of curls that the gluon will have. Different
people may prefer different densities of curls. This can effect the
appearance considerably:
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center}
    \begin{picture}(330,100)(0,0)
    \SetColor{Red}
    \Gluon(25,15)(25,95){5}{4}     \Text(25,7)[]{4 windings}
    \Gluon(95,15)(95,95){5}{5}     \Text(95,7)[]{5 windings}
    \Gluon(165,15)(165,95){5}{6}   \Text(165,7)[]{6 windings}
    \Gluon(235,15)(235,95){5}{7}   \Text(235,7)[]{7 windings}
    \Gluon(305,15)(305,95){5}{8}   \Text(305,7)[]{8 windings}
    \end{picture}
    \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
This code results in:
\begin{center}
\begin{picture}(330,100)(0,0)
\SetColor{Red}
\Gluon(25,15)(25,95){5}{4}    \Text(25,7)[]{4 windings}
\Gluon(95,15)(95,95){5}{5}    \Text(95,7)[]{5 windings}
\Gluon(165,15)(165,95){5}{6}  \Text(165,7)[]{6 windings}
\Gluon(235,15)(235,95){5}{7}  \Text(235,7)[]{7 windings}
\Gluon(305,15)(305,95){5}{8}  \Text(305,7)[]{8 windings}
\end{picture}
\end{center}
The influence of the amplitude is also rather great. The user should
experiment with it. There is however an aspect to the amplitude that
should be discussed. For a straight gluon the amplitude can determine on
which side the curls are. So does the direction of the gluon:
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center}
    \begin{picture}(325,100)(0,0)
    \SetColor{Red}
    \Gluon(50,15)(50,95){5}{6}
    \Text(50,7)[]{amp $> 0$}  \Text(40,50)[]{$\uparrow$}
    \Gluon(125,95)(125,15){5}{6}
    \Text(125,7)[]{amp $> 0$} \Text(115,50)[]{$\downarrow$}
    \Gluon(200,15)(200,95){-5}{6}
    \Text(200,7)[]{amp $< 0$} \Text(190,50)[]{$\uparrow$}
    \Gluon(275,95)(275,15){-5}{6}
    \Text(275,7)[]{amp $< 0$} \Text(265,50)[]{$\downarrow$}
    \end{picture}
    \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
The picture gets the following appearance:
\begin{center}
\begin{picture}(325,100)(0,0)
\SetColor{Red}
\Gluon(50,15)(50,95){5}{6}
\Text(50,7)[]{amp $> 0$}  \Text(40,50)[]{$\uparrow$}
\Gluon(125,95)(125,15){5}{6}
\Text(125,7)[]{amp $> 0$} \Text(115,50)[]{$\downarrow$}
\Gluon(200,15)(200,95){-5}{6}
\Text(200,7)[]{amp $< 0$} \Text(190,50)[]{$\uparrow$}
\Gluon(275,95)(275,15){-5}{6}
\Text(275,7)[]{amp $< 0$} \Text(265,50)[]{$\downarrow$}
\end{picture}
\end{center}
For straight gluons one does not need the option of the negative
amplitude. It is however necessary for gluons on an arc segment. In that
case the arc is always drawn in an anticlockwise direction. Hence the
direction is fixed and only the amplitude is left as a tool for
determining the side with the curls.

\subsection{Scaling}

Sometimes it is much easier to design a figure on a larger scale than it
is needed in the eventual printing. In that case one can use a scale
factor, either during the design or in the final result. We use the
figure in the first section as an example:
\IfColor{\textBlue}{}
\begin{verbatim}
    \vspace{-10pt} \hfill \\
    \SetScale{0.3}
    \begin{picture}(70,30)(0,13)
    \SetColor{Red}
    \GlueArc(120,50)(40,0,180){5}{8}
    \SetColor{Green}
    \GlueArc(120,50)(40,180,360){5}{8}
    \SetColor{Blue}
    \Gluon(20,50)(80,50){5}{4}  \Vertex(80,50){2}
    \Gluon(160,50)(220,50){5}{4} \Vertex(160,50){2}
    \end{picture} $+$ others
            $ = C_A(\frac{5}{3}+\frac{31}{9}\epsilon)
              + n_F(-\frac{2}{3}-\frac{10}{9}\epsilon)$
    \vspace{10pt}  \hfill \\
\end{verbatim}
\IfColor{\textBlack}{}
We have lowered the figure by 13 points (the (0,13) in the picture
statement) to make it look nice with respect to the equal sign. The
result is
    \vspace{-10pt} \hfill \\
    \SetScale{0.3}
    \begin{picture}(70,30)(0,13)
    \SetColor{Red}
    \GlueArc(120,50)(40,0,180){5}{8}
    \SetColor{Green}
    \GlueArc(120,50)(40,180,360){5}{8}
    \SetColor{Blue}
    \Gluon(20,50)(80,50){5}{4}  \Vertex(80,50){2}
    \Gluon(160,50)(220,50){5}{4} \Vertex(160,50){2}
    \end{picture} $+$ others
            $ = C_A(\frac{5}{3}+\frac{31}{9}\epsilon)
              + n_F(-\frac{2}{3}-\frac{10}{9}\epsilon)$
    \vspace{10pt}  \hfill \\
    \SetScale{1}
This way it is rather straightforward to make whole pictorial equations.
Of course some things are not scale invariant. The appreciation of a
figure may be somewhat different when the scale is changed. In the above
case one might consider changing the amplitude of the gluons a little
bit. Changing this from 5 to 7 and at the same time reducing the number
of windings from 4 to 3 for the straight gluons and from 8 to 7 for the
gluons in the arcs gives
    \vspace{-10pt} \hfill \\
    \SetScale{0.3}
    \begin{picture}(70,30)(0,13)
    \SetColor{Red}
    \GlueArc(120,50)(40,0,180){7}{7}
    \SetColor{Green}
    \GlueArc(120,50)(40,180,360){7}{7}
    \SetColor{Blue}
    \Gluon(20,50)(80,50){7}{3}  \Vertex(80,50){2}
    \Gluon(160,50)(220,50){7}{3} \Vertex(160,50){2}
    \end{picture} $+$ others
            $ = C_A(\frac{5}{3}+\frac{31}{9}\epsilon)
              + n_F(-\frac{2}{3}-\frac{10}{9}\epsilon)$
    \vspace{10pt}  \hfill \\
    \SetScale{1}
At this scale this may please the eye more.

There is one problem with scaling. Currently it is only possible to have
text scale with the rest of a figure when the text has been printed with
the PText command. This makes the typesetting more complicated, but the
scaling of the \TeX{} pixel fonts would give rather poor results anyway.

\subsection{Photons}

When drawing photons one should take care that the number of wiggles is
selected properly. Very often this number should be an integer plus
$0.5$. This can be seen in the following example:
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center}\begin{picture}(300,56)(0,0)
    \Vertex(180,10){1.5} \Vertex(120,10){1.5}
    \SetColor{Red}
    \ArrowLine(100,10)(200,10)
    \SetColor{Green}
    \LongArrowArc(150,10)(20,60,120)
    \SetColor{Brown}
    \PhotonArc(150,10)(30,0,180){4}{8.5}   % 8.5 wiggles
    \end{picture} \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
This gives the `proper' picture as it would usually drawn by hand:
    \begin{center}\begin{picture}(300,56)(0,0)
    \Vertex(180,10){1.5} \Vertex(120,10){1.5}
    \SetColor{Red}
    \ArrowLine(100,10)(200,10)
    \SetColor{Green}
    \LongArrowArc(150,10)(20,60,120)
    \SetColor{Brown}
    \PhotonArc(150,10)(30,0,180){4}{8.5}   % 8.5 wiggles
    \end{picture} \end{center}
When the number of wiggles is reduced to 8 we obtain:
    \begin{center}\begin{picture}(300,56)(0,0)
    \Vertex(180,10){1.5} \Vertex(120,10){1.5}
    \SetColor{Red}
    \ArrowLine(100,10)(200,10)
    \SetColor{Green}
    \LongArrowArc(150,10)(20,60,120)
    \SetColor{Brown}
    \PhotonArc(150,10)(30,0,180){4}{8}   % 8 wiggles
    \end{picture} \end{center}
This is not as nice. Somehow the symmetry is violated. One should also
take care that the wiggles start in the proper way. If we make the
amplitude negative we see that the photons are not `right' either:
    \begin{center}\begin{picture}(300,56)(0,0)
    \Vertex(180,10){1.5} \Vertex(120,10){1.5}
    \SetColor{Red}
    \ArrowLine(100,10)(200,10)
    \SetColor{Green}
    \LongArrowArc(150,10)(20,60,120)
    \SetColor{Brown}
    \PhotonArc(150,10)(30,0,180){-4}{8.5}   % 8.5 wiggles
    \end{picture} \end{center}
Sometimes these things require some experimenting.

\subsection{Flowcharts}

There are several commands for creating boxes with text in them. This can
be a box with either one line of text or with two lines of text. The rest
is just a matter of drawing lines and circle segments with arrows. If the
text is to scale with the picture one needs to use the postscript fonts.
The result of scaling the {\TeX} fonts is usually rather ugly, because
these fonts are pixel fonts. Here we present an example. It might describe
a system for the automatic computation of cross-sections:
\IfColor{\textBlue}{}
\begin{verbatim}
\begin{center} \begin{picture}(320,320)(0,0)
\SetPFont{Helvetica}{10}
\SetScale{0.8}
\SetColor{Magenta}
\ArrowLine(200,40)(200,10)   \ArrowLine(200,100)(200,40)
\ArrowLine(200,150)(200,100) \ArrowLine(100,130)(200,100)
\ArrowLine(85,95)(200,100)   \ArrowLine(260,105)(200,100)
\ArrowLine(250,135)(200,100) \ArrowLine(160,75)(200,100)
\ArrowLine(200,100)(250,70)  \ArrowLine(200,185)(200,150)
\ArrowLine(200,220)(200,185) \ArrowLine(200,250)(200,220)
\ArrowLine(240,263)(200,250) \ArrowLine(240,237)(200,250)
\ArrowLine(200,285)(200,250) \ArrowLine(200,310)(200,285)
\ArrowLine(200,335)(200,310) \ArrowLine(180,360)(200,335)
\ArrowLine(200,385)(180,360) \ArrowLine(50,370)(180,360)
\ArrowArc(200,247.5)(62.5,90,180)
\ArrowArc(200,247.5)(62.5,180,270)
\ArrowLine(210,385)(300,360) \ArrowLine(210,335)(300,360)
\ArrowLine(80,300)(80,130)   \ArrowLine(190,335)(80,300)
\ArrowLine(190,385)(80,300)  \ArrowLine(50,335)(80,300)
\ArrowLine(300,360)(340,340) \ArrowArcn(205,347.5)(37.5,90,270)
\SetColor{Blue}
\BCirc(200,100){10}  \BCirc(200,100){5}
\BCirc(200,40){7.5}  \BCirc(200,250){10}
\BCirc(200,250){5}   \BCirc(200,310){7.5}
\BCirc(180,360){7.5} \BCirc(80,300){7.5}
\BCirc(300,360){7.5}
\IfColor{\CCirc(200,185){7.5}{Blue}{Yellow}
}{\GCirc(200,185){7.5}{0.9}}
\SetColor{Red}
\BText(200,285){Form program} \BText(200,335){Diagrams}
\BText(200,385){Model}        \BText(200,10){events}
\BText(80,95){Axolib}         \BText(350,335){Pictures}
\IfColor{\CText(137.5,247.5){Blue}{Yellow}{instructions}
}{\GText(137.5,247.5){0.9}{instructions}}
\B2Text(260,70){Cross-sections}{Histograms}
\B2Text(140,75){Monte Carlo}{Routine}
\B2Text(275,105){FF}{1 loop integrals}
\IfColor{\C2Text(260,135){Blue}{Yellow}{Spiderlib}{Fortran/C}
}{\G2Text(260,135){0.9}{Spiderlib}{Fortran/C}}
\IfColor{\C2Text(200,150){Blue}{Yellow}{Matrix}{Element}
}{\G2Text(200,150){0.9}{Matrix}{Element}}
\B2Text(80,130){Kinematics}{Configuration}
\IfColor{\C2Text(200,220){Blue}{Yellow}{Output}{Formula}
}{\G2Text(200,220){0.9}{Output}{Formula}}
\IfColor{\C2Text(260,263){Blue}{Yellow}{Spiderlib}{Form part}
}{\G2Text(260,263){0.9}{Spiderlib}{Form part}}
\IfColor{\C2Text(260,237){Blue}{Yellow}{FF support}{library}
}{\G2Text(260,237){0.9}{FF support}{library}}
\B2Text(40,370){Reaction}{selection}
\B2Text(40,340){Specification}{Cuts, etc.}
\SetColor{Orange}
\PText(211,36)(0)[lb]{Event Generator}
\PText(211,181)(0)[lb]{Code Generator}
\PText(162,258)(0)[lb]{FORM}
\PText(211,301)(0)[lb]{Form program construction}
\PText(191,362)(0)[lb]{Diagram}
\PText(191,352)(0)[lb]{Generator}
\PText(311,370)(0)[lb]{Postscript}
\PText(311,360)(0)[lb]{Generator}
\PText(91,292)(0)[lb]{Kinematics}
\PText(91,282)(0)[lb]{Generator}
\end{picture} \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
This gives the chart
\begin{center} \begin{picture}(320,320)(0,0)
\SetPFont{Helvetica}{10}
\SetScale{0.8}
\SetColor{Magenta}
\ArrowLine(200,40)(200,10)   \ArrowLine(200,100)(200,40)
\ArrowLine(200,150)(200,100) \ArrowLine(100,130)(200,100)
\ArrowLine(85,95)(200,100)   \ArrowLine(260,105)(200,100)
\ArrowLine(250,135)(200,100) \ArrowLine(160,75)(200,100)
\ArrowLine(200,100)(250,70)  \ArrowLine(200,185)(200,150)
\ArrowLine(200,220)(200,185) \ArrowLine(200,250)(200,220)
\ArrowLine(240,263)(200,250) \ArrowLine(240,237)(200,250)
\ArrowLine(200,285)(200,250) \ArrowLine(200,310)(200,285)
\ArrowLine(200,335)(200,310) \ArrowLine(180,360)(200,335)
\ArrowLine(200,385)(180,360) \ArrowLine(50,370)(180,360)
\ArrowArc(200,247.5)(62.5,90,180)
\ArrowArc(200,247.5)(62.5,180,270)
\ArrowLine(210,385)(300,360) \ArrowLine(210,335)(300,360)
\ArrowLine(80,300)(80,130)   \ArrowLine(190,335)(80,300)
\ArrowLine(190,385)(80,300)  \ArrowLine(50,335)(80,300)
\ArrowLine(300,360)(340,340) \ArrowArcn(205,347.5)(37.5,90,270)
\SetColor{Blue}
\BCirc(200,100){10}  \BCirc(200,100){5}
\BCirc(200,40){7.5}  \BCirc(200,250){10}
\BCirc(200,250){5}   \BCirc(200,310){7.5}
\BCirc(180,360){7.5} \BCirc(80,300){7.5}
\BCirc(300,360){7.5}
\IfColor{\CCirc(200,185){7.5}{Blue}{Yellow}
}{\GCirc(200,185){7.5}{0.9}}
\SetColor{Red}
\BText(200,285){Form program} \BText(200,335){Diagrams}
\BText(200,385){Model}        \BText(200,10){events}
\BText(80,95){Axolib}         \BText(350,335){Pictures}
\IfColor{\CText(137.5,247.5){Blue}{Yellow}{instructions}
}{\GText(137.5,247.5){0.9}{instructions}}
\B2Text(260,70){Cross-sections}{Histograms}
\B2Text(140,75){Monte Carlo}{Routine}
\B2Text(275,105){FF}{1 loop integrals}
\IfColor{\C2Text(260,135){Blue}{Yellow}{Spiderlib}{Fortran/C}
}{\G2Text(260,135){0.9}{Spiderlib}{Fortran/C}}
\IfColor{\C2Text(200,150){Blue}{Yellow}{Matrix}{Element}
}{\G2Text(200,150){0.9}{Matrix}{Element}}
\B2Text(80,130){Kinematics}{Configuration}
\IfColor{\C2Text(200,220){Blue}{Yellow}{Output}{Formula}
}{\G2Text(200,220){0.9}{Output}{Formula}}
\IfColor{\C2Text(260,263){Blue}{Yellow}{Spiderlib}{Form part}
}{\G2Text(260,263){0.9}{Spiderlib}{Form part}}
\IfColor{\C2Text(260,237){Blue}{Yellow}{FF support}{library}
}{\G2Text(260,237){0.9}{FF support}{library}}
\B2Text(40,370){Reaction}{selection}
\B2Text(40,340){Specification}{Cuts, etc.}
\SetColor{Orange}
\PText(211,36)(0)[lb]{Event Generator}
\PText(211,181)(0)[lb]{Code Generator}
\PText(162,258)(0)[lb]{FORM}
\PText(211,301)(0)[lb]{Form program construction}
\PText(191,362)(0)[lb]{Diagram}
\PText(191,352)(0)[lb]{Generator}
\PText(311,370)(0)[lb]{Postscript}
\PText(311,360)(0)[lb]{Generator}
\PText(91,292)(0)[lb]{Kinematics}
\PText(91,282)(0)[lb]{Generator}
\end{picture} \end{center}

\subsection{Curves and graphs}

Axodraw is equipped with a curve fitting facility that can draw smooth
curves through a set of coordinates. Coupled to this is a set of
commands to draw the axes that are typically needed for the use of
graphs and histograms. An example of a complete picture would be
\IfColor{\textBlue}{}
\begin{verbatim}
\begin{center} \begin{picture}(360,440)(0,0)
\SetOffset(40,30)
\LinAxis(0,0)(300,0)(3,10,5,0,1.5)
\LinAxis(0,400)(300,400)(3,10,-5,0,1.5)
\LogAxis(0,0)(0,400)(4,-5,2,1.5)
\LogAxis(300,0)(300,400)(4,5,2,1.5)
\SetScale{100.} \SetWidth{0.005}
\SetColor{Blue}
\Curve{(.1057001,1.2997)(.1057003,1.5399)
(.1057006,1.6908)(.1057010,1.8019)(.1057030,2.0406)
(.1057060,2.1911)(.1057100,2.3020)(.1057300,2.5403)
(.1057600,2.6904)(.1058000,2.8007)(.1060000,3.0365)
(.1080000,3.4512)(.1100000,3.5600)(.1200000,3.6950)
(.1300000,3.6969)(.1500000,3.6308)(.1800000,3.5024)
(.2200000,3.3413)(.3000000,3.0788)(.5000000,2.6374)
(.8000000,2.2295)(1.0000000,2.0357)(1.3000000
,1.8078)(1.6000000,1.6275)(2.0000000,1.4336)
(2.5000000,1.2398)(3.0000000,1.0815)}
\SetColor{Red}
\DashCurve{(1.7853600,.0111)(1.7853800,.0228)
(1.7854000,.0339)(1.7856000,.1218)(1.7860000,.2324)
(1.7870000,.3821)(1.7900000,.5786)(1.8000000,.8089)
(1.8200000,.9765)(1.8500000,1.0869)(1.9000000
,1.1718)(2.0000000,1.2335)(2.1000000,1.2468)
(2.2000000,1.2413)(2.4000000,1.2064)
(2.7000000,1.1340)(3.0000000,1.0574)}{0.05}
\SetScale{1.}\SetWidth{0.5}
\SetColor{Blue}
\Line(200,360)(270,360)
\Text(195,360)[r]{\large$e^+e^-\rightarrow\mu^+\mu^-$}
\SetColor{Red}
\DashLine(200,330)(270,330){5}
\Text(195,330)[r]{\large$e^+e^-\rightarrow\tau^+\tau^-$}
\SetColor{Black}
\Text(0,-10)[]{0} \Text(100,-10)[]{1}
\Text(200,-10)[]{2} \Text(300,-10)[]{3}
\Text(150,-25)[]{\large Beam energy in GeV}
\Text(-10,70)[]{$1$} \Text(-10,170)[]{$10$}
\Text(-10,270)[]{$10^2$} \Text(-10,370)[]{$10^3$}
\rText(-25,220)[][l]{\Large$\sigma$ in nb}
\ArrowLine(190,270)(160,300)
\ArrowLine(160,240)(190,270)
\ArrowLine(270,300)(240,270)
\ArrowLine(240,270)(270,240)
\Photon(190,270)(240,270){4}{4.5}
\Vertex(190,270){1.5} \Vertex(240,270){1.5}
\end{picture}  \\ {\sl \hskip 10 pt Threshold
effects for $\mu$ and $\tau$} \end{center}
\end{verbatim}
\IfColor{\textBlack}{}
and the resulting picture would be
\begin{center} \begin{picture}(360,440)(0,0)
\SetOffset(40,30)
\LinAxis(0,0)(300,0)(3,10,5,0,1.5)
\LinAxis(0,400)(300,400)(3,10,-5,0,1.5)
\LogAxis(0,0)(0,400)(4,-5,2,1.5)
\LogAxis(300,0)(300,400)(4,5,2,1.5)
\SetScale{100.} \SetWidth{0.005}
\SetColor{Blue}
\Curve{(.1057001,1.2997)(.1057003,1.5399)
(.1057006,1.6908)(.1057010,1.8019)(.1057030,2.0406)
(.1057060,2.1911)(.1057100,2.3020)(.1057300,2.5403)
(.1057600,2.6904)(.1058000,2.8007)(.1060000,3.0365)
(.1080000,3.4512)(.1100000,3.5600)(.1200000,3.6950)
(.1300000,3.6969)(.1500000,3.6308)(.1800000,3.5024)
(.2200000,3.3413)(.3000000,3.0788)(.5000000,2.6374)
(.8000000,2.2295)(1.0000000,2.0357)(1.3000000
,1.8078)(1.6000000,1.6275)(2.0000000,1.4336)
(2.5000000,1.2398)(3.0000000,1.0815)}
\SetColor{Red}
\DashCurve{(1.7853600,.0111)(1.7853800,.0228)
(1.7854000,.0339)(1.7856000,.1218)(1.7860000,.2324)
(1.7870000,.3821)(1.7900000,.5786)(1.8000000,.8089)
(1.8200000,.9765)(1.8500000,1.0869)(1.9000000
,1.1718)(2.0000000,1.2335)(2.1000000,1.2468)
(2.2000000,1.2413)(2.4000000,1.2064)
(2.7000000,1.1340)(3.0000000,1.0574)}{0.05}
\SetScale{1.}\SetWidth{0.5}
\SetColor{Blue}
\Line(200,360)(270,360)
\Text(195,360)[r]{\large$e^+e^-\rightarrow\mu^+\mu^-$}
\SetColor{Red}
\DashLine(200,330)(270,330){5}
\Text(195,330)[r]{\large$e^+e^-\rightarrow\tau^+\tau^-$}
\SetColor{Black}
\Text(0,-10)[]{0} \Text(100,-10)[]{1}
\Text(200,-10)[]{2} \Text(300,-10)[]{3}
\Text(150,-25)[]{\large Beam energy in GeV}
\Text(-10,70)[]{$1$} \Text(-10,170)[]{$10$}
\Text(-10,270)[]{$10^2$} \Text(-10,370)[]{$10^3$}
\rText(-25,220)[][l]{\Large$\sigma$ in nb}
\ArrowLine(190,270)(160,300)
\ArrowLine(160,240)(190,270)
\ArrowLine(270,300)(240,270)
\ArrowLine(240,270)(270,240)
\Photon(190,270)(240,270){4}{4.5}
\Vertex(190,270){1.5} \Vertex(240,270){1.5}
\end{picture}  \\ {\sl \hskip 10 pt Threshold
effects for $\mu$ and $\tau$} \end{center}
Of course one can scale these pictures further, but because the scale
factor has been used to enter the data points these should then be
adapted too. Note that when the scale is blown up by a factor 100, the
linewidth has to be scaled down or disasters will take place.

Finally a playful example:
\IfColor{\textBlue}{}
\begin{verbatim}
    \begin{center}\begin{picture}(300,56)(0,0)
    \SetColor{Blue}
    \Line(100,25)(150,25)
    \SetColor{Green}
    \Gluon(150,25)(200,25){3}{6}
    \SetColor{Red}
    \Photon(150,35)(200,45){3}{6}
    \SetColor{Mahogany}
    \ZigZag(150,15)(200,5){3}{6}
    \IfColor{\COval(150,25)(20,10)(0){Black}{Yellow}
         }{\GOval(150,25)(20,10)(0){0.5}}
    \end{picture} \end{center}
\end{verbatim}
\IfColor{\textBlack{}}{}which results in
    \begin{center}\begin{picture}(300,56)(0,0)
    \SetColor{Blue}
    \Line(100,25)(150,25)
    \SetColor{Green}
    \Gluon(150,25)(200,25){3}{6}
    \SetColor{Red}
    \Photon(150,35)(200,45){3}{6}
    \SetColor{Mahogany}
    \ZigZag(150,15)(200,5){3}{6}
    \IfColor{\COval(150,25)(20,10)(0){Black}{Yellow}
         }{\GOval(150,25)(20,10)(0){0.5}}
    \end{picture} \end{center}

Acknowledgement: The author wishes to thank G.J.van Oldenborgh for help
with some of the \TeX{} macros.

Axodraw can be obtained from the authors homepage:
\IfColor{\textOliveGreen}{}{http://norma.nikhef.nl/$\sim$t68/axodraw}~
{\IfColor{\textBlack}{}$\!\!\!\!$.}
Alternatively it is available by means of anonymous ftp from ftp.nikhef.nl.
There it is located in the directory pub/form/axodraw. Commentary and
suggestions should be sent to the author at t68\verb:@:nikhef.nl.
\end{document}
