# from sage.calculus.desolvers import desolve_odeint
x,y=var('x,y')
mu =-2 # de trage richting in knooppunt (0,0) met mu<0 verandert rond mu=-1
f=[mu*x-x^2,-y]
p1=plot_vector_field(f,(x,-abs(mu)-1,abs(mu)+1),(y,-2,2))
sol=desolve_odeint(f,[-mu+0.2,1],srange(0,10,0.1),[x,y])
p2=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu,2],srange(0,10,0.1),[x,y])
p3=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu/2,2],srange(0,10,0.1),[x,y])
p4=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu+0.1,2],srange(0,10,0.1),[x,y])
p5=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu-0.1,2],srange(0,1,0.1),[x,y])
p6=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[-mu,2],srange(0,10,0.1),[x,y])
p7=line(zip(sol[:,0],sol[:,1]))
show(p1+p2+p3+p4+p5+p6+p7)
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# from sage.calculus.desolvers import desolve_odeint
x,y=var('x,y')
mu=0.5 # de trage richting in knooppunt (mu,0) met mu>0 verandert rond mu=1
f=[mu*x-x^2,-y]
p1=plot_vector_field(f,(x,-abs(mu)-1,abs(mu)+1),(y,-2,2))
sol=desolve_odeint(f,[-mu+0.2,1],srange(0,0.3,0.1),[x,y])
p2=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu,2],srange(0,1,0.1),[x,y])
p3=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu/2,2],srange(0,10,0.1),[x,y])
p4=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu+0.1,2],srange(0,10,0.1),[x,y])
p5=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[mu-0.1,2],srange(0,1,0.1),[x,y])
p6=line(zip(sol[:,0],sol[:,1]))
sol=desolve_odeint(f,[-mu,2],srange(0,0.3,0.1),[x,y])
p7=line(zip(sol[:,0],sol[:,1]))
show(p1+p2+p3+p4+p5+p6+p7)
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