If have implemented an animation for the Clifford attractor
xn+1 = sin(a yn) + c cos(a xn)
yn+1 = sin(b xn) + d cos(b yn)
The animation varies the parameters and indicates this through a moving red disk.
To get a back and for movement I have introduced a step direction which is flipped each time maxframes was reached, i.e. the counter has value 0.
Unfortunately the animate function seems - or is - called always twice, why?
I have covered this problem and now there is the main problem!
Only one wy is stored in the movie ...
a,b,c,d = -1.4, 1.6, 1.0, 0.7 # Parameter
xmin,xmax,ymin,ymax=-2,2.5,-2,2
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation as ani
from timeit import default_timer as timer
fig, ax = plt.subplots(figsize=(6,6))
nmax=15000; x0,y0=xmin,ymin
XYc = np.zeros((nmax,3))
maxframes=200
deltax=(xmax-xmin)/maxframes
deltay=(ymax-ymin)/maxframes
Deltapar = 1
deltapar = 2*Deltapar/maxframes
amin,bmin,cmin,dmin = a-Deltapar, b-Deltapar, c-Deltapar, d-Deltapar
amax,bmax,cmax,dmax = a+Deltapar, b+Deltapar, c+Deltapar, d+Deltapar
from numba import jit
@jit
def iteration(a,b,c,d,x,y,XYc):
XYc[0]=x,y,x-x
for i in range(1,nmax):
x,y = np.sin(a*y) + c*np.cos(a*x),np.sin(b*x) + d*np.cos(b*y)
XYc[i]=x,y,i/nmax
iteration(a,b,c,d,x0,y0,XYc)
title='Clifford Attractor: a=%.2f, b=%.2f, c=%.2f, d=%.2f'%(a,b,c,d)
ax.set_title(title)
ax.set_xlim(xmin,xmax)
ax.set_ylim(ymin,ymax)
plt.tight_layout()
myCmap = plt.cm.get_cmap('gist_ncar_r')
dots,=ax.plot(XYc[:,0],XYc[:,1],",",linewidth=0.1)
dotm,=ax.plot([xmin],[ymin], marker="o", color="r")
step=1
anicount=0
def animate(i):
global anicount, step
if i==0:
anicount+=1
if anicount%2==0: step = -step
print("#",anicount," ",step)
if step==1:
am=amin+i*deltapar
xm=xmin+i*deltax
ym=ymin+i*deltay
else:
am=amax-i*deltapar
xm=xmax-i*deltax
ym=ymax-i*deltay
iteration(am,b,c,d,x0,y0,XYc)
dots.set_data(XYc[:,0],XYc[:,1])
dotm.set_data([xm],[ym])
return dotm, dots,
anim = ani.FuncAnimation(
fig, animate, frames=maxframes, interval=10, blit=True)
fname='cliffordattr'
#anim.save(fname+'.mp4')
#plt.savefig(fname+'.jpg')
#plt.savefig(fname+'.eps')
plt.show()
I have tried to use the extra_anim=[...,...] option for savefig
anim1.save(fname+'1.mp4', fps=30)
anim2.save(fname+'2.mp4', fps=30)
anim1.save(fname+'12.mp4', fps=30,extra_anim=[anim1,anim2,])
But still only one direction gets to the movie.
- How can I save several animate cycles in one movie???
- How can I save different animations in one movie??
- Why is animate called twice?
Any help is appreciated
