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Contents 1 Raster images 1.1 2D images 1.2 3D images 2 Vector images 2.1 Notes 2.2 Direct method 2.2.1 First example 2.2.2 Basic svg functions 2.3 Using Gnuplot 2.3.1 Using Gnuplot thru Plot package 2.3.2 Using Gnuplot thru Draw package 3 See also 4 Notes and references

Raster images

2D images

Julia set and external rays landing on parabolic period 2-cycle

2D view of Julia set ( black points) and its critical orbit ( red points)

2D view of forward orbit of critical point of complex quadratic polynomial

Centers of 983 hyperbolic components of Mandelbrot set with respect to complex quadratic polynomial for period 1-10

Apollonian gasket

3D images

Forward orbit of critical point of complex quadratic polynomial tending to weakly attracting fixed point.

3D view of 2D Julia set where third dimension is distribution of points of inverse orbit of crtitical point for complex quadratic polynomial.

Vector images

Topologicla model of Mandelbrot set ( here is png version because now it is not allowed to upload svg files)

How to make vector svg images instead of rasterpng files ?

Notes

• it is not permitted to upload svg images to Maxima wiki now (:-(
• svg images which are made of lot of elements need a long time to load ( raster version is loade much quicker )

Direct method

Here svg file is directly created

First example

cmWidth:10;
cmHeight:10;
iWidth:800;
iHeight:600;
radius:200;
center_x:400;
center_y:300;
f_name:"a.svg";
f : openw (f_name);
printf(f, "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>~%");
printf(f, "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\"~%\"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">~%");
printf(f,"<svg width=\"~d cm\" height=\"~d cm\" viewBox=\"0 0 ~d ~d\" xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\">~%",
cmWidth,cmHeight,iWidth,iHeight);
printf(f,"<circle cx=\"~f\" cy=\"~f\" r=\"~f\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"/>~%",center_x,center_y,radius);
printf(f,"</svg>~%");
close (f);

Above code draws circle usung circle svg command.

Basic svg functions

BeginSVG(file_name,cm_width,cm_height,i_width,i_height):=
block(
 destination : openw (file_name),
 printf(destination, "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>~%"),
 printf(destination, "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\"~%\"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">~%"),
 printf(destination,"<svg width=\"~dcm\" height=\"~dcm\" viewBox=\"0 0 ~d ~d\" xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\">~%",
 cm_width,cm_height,i_width,i_height),
 return(destination)
);
CircleSVG(dest,center_x,center_y,_radius,_strokeWidth):=
 printf(dest,"<circle cx=\"~f\" cy=\"~f\" r=\"~f\" fill=\"white\" stroke=\"black\" stroke-width=\"~f\"/>~%",
 center_x,center_y,_radius,_strokeWidth);
EndSVG(destination):=
(
printf(destination,"</svg>~%"),
close (destination)
);

And example of use :

f:BeginSVG("a.svg",30,20,800,600);
circleSVG(f,100,100,50,1);
EndSVG(f);

It maybe usefull for drawing images made of circles, like :

• circle packings
• Kleinian groups

Using Gnuplot

Gnuplot creates svg not correctly:

• one must add manually </svg> at the end of the svg file
• if you want to draw circles svg image does not use circle element, but path. It maybe important when one have to draw many ( like thousands) of circles.

Using Gnuplot thru Plot package

Functions plot2d, plot3d and contour_plot arre defind in plot package ( file plot.lisp ), which is automaticaly loaded.

set_plot_option([plot_format, gnuplot]);
set_plot_option([nticks, 80]);
set_plot_option([gnuplot_term, svg]);
set_plot_option([gnuplot_out_file, "circle.svg"]);
plot2d ([parametric, cos(t), sin(t),[t,-%pi,%pi]])$

Here is sample image.

Using Gnuplot thru Draw package

"This terminal is not directly supported by draw, but you can use the 'user_preamble' option to force output in svg format." <ref>Mario Rodriguez proposition in discussion about discrete dynamical system on the Maxima mailing list</ref>

Here is an example:

load(draw);
draw2d(explicit(exp(x)-1,x,-1,1),user_preamble=["set terminal svg","set out 'mysvg.svg'"]);

Here is png image and its svg version.

See also

• Introduction to Dynamical Systems: A Hands-on Approach with Maxima. A free book by Jaime E. Villate, ISBN 972-99396-0-8, Porto, Portugal, 2007.
• Images made with draw package ( interface to Gnuplot)
• Wiki Commons Category : Created with Maxima software
• 49.1 Introduction to dynamics package
• Package fractals repository

Notes and references

<references/>