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

-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

XPPHELP

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.

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:

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.