Differences between revisions 52 and 53
Revision 52 as of 2012-01-17 14:54:45
Size: 12143
Editor: mhampton
Comment:
Revision 53 as of 2012-01-17 14:56:34
Size: 12144
Editor: mhampton
Comment:
Deletions are marked like this. Additions are marked like this.
Line 280: Line 280:
=== Integral Curvature Apollonian Circle Packing by Marshall Hampton and Carl Witty === === Integral Curvature Apollonian Circle Packing ===
by Marshall Hampton and Carl Witty

Pictures drawn by Sage

These pictures and images were drawn by Sage.

Everywhere continuous, nowhere differentiable function

  • Everywhere continuous, nowhere differentiable function (in the infinite limit, anyway):

p = Graphics()
for n in range(1,20):
  f = lambda x: sum([sin(x*3^i)/(2^i) for i in range(1,n)])
  p += plot(f,0,float(pi/3),plot_points=2000,rgbcolor=hue(n/20))

p.show(xmin=0, ymin=0,dpi=250)

cool pic 1

Mirrored balls in tachyon

t = Tachyon(camera_center=(8.5,5,5.5), look_at=(2,0,0), raydepth=6, xres=1500, yres=1500)
t.light((10,3,4), 1, (1,1,1))
t.texture('mirror', ambient=0.05, diffuse=0.05, specular=.9, opacity=0.9, color=(.8,.8,.8))
t.texture('grey', color=(.8,.8,.8), texfunc=7) ## try other values of texfunc too!
t.plane((0,0,0),(0,0,1),'grey')
t.sphere((4,-1,1), 1, 'mirror')
t.sphere((0,-1,1), 1, 'mirror')
t.sphere((2,-1,1), 0.5, 'mirror')
t.sphere((2,1,1), 0.5, 'mirror')
show(t)

cool ray tracing pic

Math art by Tom Boothby

# Author: Tom Boothby
# This is a remake of an old art piece I made in POVRay


t = Tachyon(xres=1000,yres=600, camera_center=(1,0,5), antialiasing=3)
t.light((4,3,2), 0.2, (1,1,1))
t.texture('t0', ambient=0.1, diffuse=0.9, specular=0.5, opacity=1.0, color=(1.0,1,1))
t.texture('t1', ambient=0.5, diffuse=0.5, specular=0.0, opacity=1.0, color=(0,0,0))
t.texture('t2', ambient=0.2, diffuse=0.7, specular=0, opacity=0.7, color=(.5,.5,.5))
t.texture('t3', ambient=.9, diffuse=5, specular=0,opacity=.1, color=(1,0,0))
t.sphere((1,0,0), 30, 't2')



k=0
for i in srange(-pi*10,0,.01):
  k += 1
  t.sphere((cos(i/10)-.1, sin(i/10)*cos(i), sin(i/10)*sin(i)), 0.1, 't0')
  t.sphere((cos(i/10) + 2.1, sin(i/10)*cos(i), sin(i/10)*sin(i)), 0.1, 't1')

t.show(verbose=1)

cool pic 2

Twisted cubic in tachyon

t = Tachyon(xres=512,yres=512, camera_center=(5,0,0))
t.light((4,3,2), 0.2, (1,1,1))
t.texture('t0', ambient=0.1, diffuse=0.9, specular=0.5, opacity=1.0, color=(1.0,0,0))
t.texture('t1', ambient=0.1, diffuse=0.9, specular=0.3, opacity=1.0, color=(0,1.0,0))
t.texture('t2', ambient=0.2, diffuse=0.7, specular=0.5, opacity=0.7, color=(0,0,1.0))
k=0
for i in srange(-5,1.5,0.1):
    k += 1
    t.sphere((i,i^2-0.5,i^3), 0.1, 't%s'%(k%3))

t.show()

cool pic 3

Reflections from four spheres in tachyon

t6 = Tachyon(camera_center=(0,-4,1), xres = 800, yres = 600, raydepth = 12, aspectratio=.75, antialiasing = True)
t6.light((0.02,0.012,0.001), 0.01, (1,0,0))
t6.light((0,0,10), 0.01, (0,0,1))
t6.texture('s', color = (.8,1,1), opacity = .9, specular = .95, diffuse = .3, ambient = 0.05)
t6.texture('p', color = (0,0,1), opacity = 1, specular = .2)
t6.sphere((-1,-.57735,-0.7071),1,'s')
t6.sphere((1,-.57735,-0.7071),1,'s')
t6.sphere((0,1.15465,-0.7071),1,'s')
t6.sphere((0,0,0.9259),1,'s')
t6.plane((0,0,-1.9259),(0,0,1),'p')
t6.show()

fourspheres.png

A cone inside a sphere

sage: u,v = var("u,v")
sage: p1 = parametric_plot3d([cos(u)*v, sin(u)*v, 3*v/2-1/3], (u, 0, 2*pi), (v, 0, 0.95),plot_points=[20,20])
sage: p2 = sphere((0,0,2/3), color='red', opacity=0.5, aspect_ratio=[1,1,1])
sage: show(p1+p2)

http://sage.math.washington.edu/home/wdj/art/cone-inside-sphere.jpg

A cylinder inside a cone

sage: u,v = var("u,v")
sage: p1 = parametric_plot3d([cos(u)*v, sin(u)*v, 3/2-3*v/2], (u, 0, 2*pi), (v, 0, 1.5), opacity = 0.5, plot_points=[20,20])
sage: p2 = parametric_plot3d([cos(u)/2, sin(u)/2, v-3/4], (u, 0, 2*pi), (v, 0, 3/2), plot_points=[20,20])
sage: show(p1+p2)

http://sage.math.washington.edu/home/wdj/art/cylinder-inside-cone.jpg

A hypotrochoid animation by Dean Moore

Hypotrochoid. Written by Dean Moore, February 2008

This animation was moved to the section on the animate command : http://wiki.sagemath.org/animate#AhypotrochoidanimationbyDeanMoore

A simpler hypotrochoid

This animation was moved to the section on the animate command : http://wiki.sagemath.org/animate#Asimplerhypotrochoid

The witch of Maria Agnesi

by Marshall Hampton

This animation was moved to the section on the animate command : http://wiki.sagemath.org/animate#ThewitchofMariaAgnesi

p-adic Seasons Greetings

  • I know this is early, but thanks to Robert Bradshaw's p-adic plot function, here is a p-adic Seasons Greetings:

http://sage.math.washington.edu/home/wdj/art/padic-seasons-greetings.png

This is the code:

sage: P1 = Zp(3).plot(rgbcolor=(0,1,0))
sage: P2 = Zp(7).plot(rgbcolor=(1,0,0))
sage: P3 = text("$Seasons$ $Greetings$ ",(0.0,1.8))
sage: P4 = text("$from$ $everyone$ $at$ sagemath.org!",(0.1,-1.6))
sage: (P1+P2+P3+P4).show(axes=False)

Lorentz butterfly

"""
Draws Loretz butterfly using matplotlib (2d) or jmol (3d).
Written by Matthew Miller and William Stein.

"""

def butterfly2d():
    """"
    EXAMPLE:
        sage: butterfly2d()
    """    
    g = Graphics()
    x1, y1 = 0, 0
    from math import sin, cos, exp, pi
    for theta in srange( 0, 10*pi, 0.01 ):
        r = exp(cos(theta)) - 2*cos(4*theta) + sin(theta/12)^5
        x = r * cos(theta)  # Convert polar to rectangular coordinates
        y = r * sin(theta)
        xx = x*6 + 25       # Scale factors to enlarge and center the curve.
        yy = y*6 + 25
        if theta != 0: 
            l = line( [(x1, y1), (xx, yy)], rgbcolor=hue(theta/7 + 4) )
            g = g + l
            x1, y1 = xx, yy
    g.show(dpi=100, axes=False)

def butterfly3d():
    """"
    EXAMPLE:
        sage: butterfly3d()
    """    
    g = point3d((0,0,0))
    x1, y1 = 0, 0
    from math import sin, cos, exp, pi
    for theta in srange( 0, 10*pi, 0.05):
        r = exp(cos(theta)) - 2*cos(4*theta) + sin(theta/12)^5
        x = r * cos(theta)  # Convert polar to rectangular coordinates
        y = r * sin(theta)
        xx = x*6 + 25       # Scale factors to enlarge and center the curve.
        yy = y*6 + 25
        if theta != 0:
            l = line3d( [(x1, y1, theta), (xx, yy, theta)],
            rgbcolor=hue(theta/7 + 4) )
            g = g + l
            x1, y1 = xx, yy
    g.show(dpi=100, axes=False)

http://sage.math.washington.edu/home/wdj/art/butterfly2d.png

http://sage.math.washington.edu/home/wdj/art/butterfly3d.png

Feigenbaum diagram

Author: Pablo Angulo Posted to sage-devel 2008-09-13. See also https://sage.math.washington.edu:8101/home/pub/3 #Note: Mandelbrot set moved to interact/fractals

#Plots Feigenbaum diagram: divides the parameter interval [2,4] for mu
#into N steps. For each value of the parameter, iterate the discrete
#dynamical system x->mu*x*(1-x), drop the first M1 points in the orbit
#and plot the next M2 points in a (mu,x) diagram

N=200
M1=200
M2=200
x0=0.509434

puntos=[]
for t in range(N):
   mu=2.0+2.0*t/N
   x=x0
   for i in range(M1):
       x=mu*x*(1-x)
   for i in range(M2):
       x=mu*x*(1-x)
       puntos.append((mu,x))
point(puntos,pointsize=1)

feigenbaum.png

Sierpinski triangle

  • This was a black+white Sierpinski triangle coded by Marshall Hampton, with some slight tweeking by David Joyner to add colors:

def sierpinski_seasons_greetings():
    """
    Code by Marshall Hampton.
    Colors by David Joyner.
    General depth by Rob Beezer.
    Copyright Marshall Hampton 2008, licensed
    creative commons, attribution share-alike.
    """
    depth = 7
    nsq = RR(3^(1/2))/2.0
    tlist_old = [[[-1/2.0,0.0],[1/2.0,0.0],[0.0,nsq]]]
    tlist_new = tlist_old[:]
    for ind in range(depth):
       for tri in tlist_old:
           for p in tri:
               new_tri = [[(p[0]+x[0])/2.0, (p[1]+x[1])/2.0] for x in tri]
               tlist_new.append(new_tri)
       tlist_old = tlist_new[:]
    T = tlist_old
    N  = 4^depth
    N1 = N - 3^depth
    q1 = sum([line(T[i]+[T[i][0]], rgbcolor = (0,1,0)) for i in range(N1)])
    q2 = sum([line(T[i]+[T[i][0]], rgbcolor = (1,0,0)) for i in range(N1,N)])
    show(q2+q1, figsize = [6,6*nsq], axes = False)

GIMP was used to add a Season's greetings message:

http://sage.math.washington.edu/home/wdj/art/sierpinski-seasons-greetings-from-sage.png

Also (thanks to Rob Beezer) available in poster form in pdf format: http://sage.math.washington.edu/home/wdj/art/seasons-greetings-sage.pdf, and in A4 size: http://sage.math.washington.edu/home/wdj/art/seasons-greetings-sage-a4.pdf.

The Tamer and the Lion by Provencal and Labbe

This animation was moved to the section on the animate command : http://wiki.sagemath.org/animate#TheTamerandtheLionbyProvencalandLabbe

Integral Curvature Apollonian Circle Packing

by Marshall Hampton and Carl Witty

def kfun(k1,k2,k3,k4):
    """
    The Descartes formula for the curvature of an inverted tangent circle.
    """
    return 2*k1+2*k2+2*k3-k4


colorlist = [(1,0,1),(0,1,0),(0,0,1),(1,0,0)]

def circfun(c1,c2,c3,c4):
    """
    Computes the inversion of circle 4 in the first three circles.
    """
    newk = kfun(c1[3],c2[3],c3[3],c4[3])
    newx = (2*c1[0]*c1[3]+2*c2[0]*c2[3]+2*c3[0]*c3[3]-c4[0]*c4[3])/newk
    newy = (2*c1[1]*c1[3]+2*c2[1]*c2[3]+2*c3[1]*c3[3]-c4[1]*c4[3])/newk
    newcolor = c4[4]
    if newk > 0:
        newr = 1/newk
    elif newk < 0:
        newr = -1/newk
    else:
        newr = Infinity
    return [newx, newy, newr, newk, newcolor]

def mcircle(circdata, label = False, thick = 1/10, cutoff = 2000, color = ''):
    """
    Draws a circle from the data.  label = True
    """
    if color == '':
        color = colorlist[circdata[4]]
    if label==True and circdata[3] > 0 and circdata[2] > 1/cutoff:
        lab = text(str(circdata[3]),(circdata[0],circdata[1]), fontsize = \
500*(circdata[2])^(.95), vertical_alignment = 'center', horizontal_alignment \
= 'center', rgbcolor = (0,0,0),zorder=10)
    else:
        lab = Graphics()
    circ = circle((circdata[0],circdata[1]), circdata[2], rgbcolor = (0,0,0), \
thickness = thick)
    circ = circ + circle((circdata[0],circdata[1]), circdata[2], rgbcolor = color, \
thickness = thick, fill=True, alpha = .4, zorder=0)
    return lab+circ

def add_circs(c1, c2, c3, c4, cutoff = 300):
    """
    Find the inversion of c4 through c1,c2,c3.  Add the result to circlist,
    then (if the result is big enough) recurse.
    """
    newcirc = circfun(c1, c2, c3, c4)
    if newcirc[3] < cutoff:
        circlist.append(newcirc)
        add_circs(newcirc, c1, c2, c3, cutoff = cutoff)
        add_circs(newcirc, c2, c3, c1, cutoff = cutoff)
        add_circs(newcirc, c3, c1, c2, cutoff = cutoff)

zst1 = [0,0,1/2,-2,0]
zst2 = [1/6,0,1/3,3,1]
zst3 = [-1/3,0,1/6,6,2]
zst4 = [-3/14,2/7,1/7,7,3]

circlist = [zst1,zst2,zst3,zst4]
add_circs(zst1,zst2,zst3,zst4,cutoff = 500)
add_circs(zst2,zst3,zst4,zst1,cutoff = 500)
add_circs(zst3,zst4,zst1,zst2,cutoff = 500)
add_circs(zst4,zst1,zst2,zst3,cutoff = 500)

circs = sum([mcircle(q, label = True, thick = 1/2) for q in \
circlist[1:]])
circs = circs + mcircle(circlist[0],color=(1,1,1),thick=1)
circs.save('./Apollonian3.png',axes = False, figsize = [12,12], xmin = \
-1/2, xmax = 1/2, ymin = -1/2, ymax = 1/2)

Apollonian.png

pics (last edited 2017-03-26 02:08:05 by mrennekamp)