NAME

xppaut - X Phase plane plus AUTO. Solves many kinds of equations.

SYNOPSIS

xppaut [-silent] [-xorfix] [-convert]

: [-newseed] [-ee] [-allwin]
: [-white] [-setfile file] [-runnow]
: [-bigfont font] [-smallfont font] [-parfile file]
: [-outfile file] [-icfile file] [-grads boolean] [-bell boolean]
: [-forecolor color] [-backcolor color] [-backimage image]
: [-quiet boolean] [-logfile file] [-internset boolean] [-uset setname]
: [-rset setname] [-include file] [-qics] [-qpars] [-qsets]
: [-anifile file] [file...]

DESCRIPTION

xppaut is a tool for solving:

differential equations
difference equations
delay equations
functional equations
differential-algebraic equation
boundary value problems
stochastic equations

The code brings together a number of useful algorithms and is written in C. All the graphics and interface are created using the X Window System protocol client library Xlib <http://www.xfree86.org>.

xppaut capabilities:

Handles up to 1950 differential equations.
There are over a dozen solvers including several for stiff systems, a solver for integral equations and a symplectic solver
Up to 10 graphics windows can be visible at once and a variety of color combinations is supported
PostScript output is supported as well as GIF and animated GIF movies
Post processing is easy and includes the ability to make histograms, FFTs and applying functions to columns of data
Equilibria and linear stability as well as one-dimensional invariant sets can be computed
Nullclines and flow fields aid in the qualitative understanding of two-dimensional models
Poincare maps and equations on cylinders and tori are also supported
Some useful averaging theory tricks and various methods for dealing with coupled oscillators
Equations with Dirac delta functions are allowable
Animations of simulations such as a little pendulum moving back and forth or lamprey swimming
A curve-fitter based on the Marquardt-Levenberg algorithm which lets you fit dynamical systems to data
Generate "movies" of three-dimensional views of attractors or parametric changes in the attractor as some parameters vary
Dynamically link to external subroutines
From the command line type /dev/stdin as the file and you can write the ODE on the fly

OPTIONS

-silent: Batch run without the interface and dump solutions to a file
-xorfix: Work-around for exclusive Or with X on some monitors/graphics setups
-convert: Convert old style ODE files (e.g. phaseplane) to new ODE style
-newseed: Randomizes the random number generator which will often use the same seed
-ee: Emulates shortcuts of Evil Empire style (MS)
-allwin: Brings XPP up with all the windows visible
-white: Swaps foreground and background colors
-setfile filename: Loads the set file before starting up
-runnow: Runs ode file immediately upon startup (implied by -silent)
-bigfont font: Use the big font whose filename is given
-smallfont font: Use the small font whose filename is given
-parfile filename: Load parameters from the named file
-outfile filename: Send output to this file (default is output.dat)
-icfile filename: Load initial conditions from the named file
-forecolor color: Hexadecimal color (e.g. 000000) for foreground
-backcolor color: Hexadecimal color (e.g. EDE9E3) for background
-mwcolor color: Hexadecimal color (e.g. 808080) for main window
-dwcolor color: Hexadecimal color (e.g. FFFFFF) for drawing window
-backimage filename: Name of bitmap file (.xbm) to tile in background

For example, the following text saved to a file named stipple2.xbm can be loaded to impart a stippled background.

#define stipple2_width 2

#define stipple2_height 2

static char stipple2_bits[] = {

0x02,0x01};

-grads B: Color gradients will (B=1) or will not (B=0) be used
-width N: Minimum width in pixels of main window
-height N: Minimum height in pixels of main window
-bell B: System bell on events will (B=1) or will not (B=0) be used
-internset B: Internal sets will (B=1) or will not (B=0) be run during batch run
-uset setname: Named internal set will be run during batch run
-rset setname: Named internal set will not be run during batch run
-include filename: Named file will be included (see include directive)
-qsets: Query internal sets (output saved to OUTFILE)
-qpars: Query parameters (output saved to OUTFILE)
-qics: Query initial conditions (output saved to OUTFILE)
-quiet B: Verbose log messages will (B=0) or will not be (B=1) written
-logfile filename: Verbose log messages are written to named file instead of stdout
-anifile filename: Load animation (.ani) from the named file

ENVIRONMENT

XPPSTART

File browser will open to the specified path. This may be useful in an instructional setting to point to a mapped drive containing course materials.

XPPHELP

Path to the XPPAUT documentation file <xpphelp.html> (e.g. /usr/share/doc/xppaut/html/xpphelp.html)

XPPBROWSER: Web browser to view documentation (e.g. /usr/bin/firefox)

FILES

Each user can customize the behavior and appearance of Xppaut via the file “$HOME/.xpprc”. Where the environment variable $HOME points to the user's home directory. On most systems $HOME will already be set. Each option line in .xpprc begins with the “@” symbol followed by a comma-separated list of options. Comment lines begin with the “#” symbol and are ignored.

# Example .xpprc file

@ maxstor=50000

@ meth=qualrk,tol=1e-6,atol=1e-6

#Set up a customized look

@ but=quit:fq,bell=1

@ bigfont=lucidasanstypewriter-bold-14,grads=1

# thats it

An list of the extensive options are given below. For complete description of each of these options the reader is referred to the technical documentation for Xppaut.

ATOL, AUTOEVAL, AUTOVAR, AUTOXMAX, AUTOXMIN, AUTOYMAX, AUTOYMIN, AXES, BACK, BACKCOLOR, BACKIMAGE, BANDLO, BANDUP, BELL, BIGFONT, BOUND, BUT, COLORMAP, DELAY, DLL_FUN, DLL_LIB, DS, DSMAX, DSMIN, DT, DTMAX, DTMIN, DWCOLOR, EPSL, EPSS, EPSU, FOLD, FORECOLOR, GRADS, HEIGHT, JAC_EPS, LOGFILE, LT, MAXSTOR, METH, MWCOLOR, NCOL, NEWT_ITER, NEWT_TOL, NJMP, NMAX, NMESH, NORMMAX, NORMMIN, NPLOT, NPR, NTST, OUT, OUTPUT, PARMAX, PARMIN, PHI, POIMAP, POIPLN, POISGN, POISTOP, POIVAR, PS_COLOR, PS_FONT, PS_FSIZE, PS_LW, QUIET, RANGE, RANGEHIGH, RANGELOW, RANGEOLDIC, RANGEOVER, RANGERESET, RANGESTEP, RUNNOW, SEC, SEED, SMALLFONT, SMC, SPC, STOCH, T0, THETA, TOL, TOR_PER, TOTAL, TRANS, UEC, UMC, UPC, VMAXPTS, WIDTH, XHI, XLO, XMAX, XMIN, XNC, XP#, YHI, YLO, YMAX, YMIN, YNC, YP#, ZMAX, ZMIN, ZP#,

HELP

Note: On typical X Window installations the command xlsfonts lists available fonts. For example, the following command lists only the available fixed width fonts:

xlsfonts | grep -i -e "typewriter" \

-e "mono" -e "^[0-9]x[0-9]" \

-e "fixed" -e "-c-" -e "-m-" | sort

Note: For a listing of standard hexadecimal colors see <http://en.wikipedia.org/wiki/Web_colors>.

AUTHOR

This manual page was written by Isaac Jones <ijones@syntaxpolice.org>, for the Debian GNU/Linux system on March 4, 2002. This man page was updated by D. P. Dougherty on Jan 4, 2011. This man page was updated by B. Ermentrout on Feb 26, 2011.