def main():
# DATI
a = 3
Omega = 0.8
O2 = Omega**2
xie = 0.1
xig = 0.5
ra = sqrt(0.25)
Nelem = 119
NWake = (Nelem+1)//2*10
rt = 0.1
M = array([[1, xig],[xig, ra**2+2*xig*xie-xie**2]])
K = array([[O2, O2*xie],[O2*xie, ra**2+O2*xie**2]])
I = complex(0,1)
karr = linspace(0.2,1,100)
z1 = []
z2 = []
kg = []
for k in karr:
E = ematrixwing(Nelem, NWake, rt, I*k)/(2.*pi)
#print E
A = -dot(inv(K),(M + 1./(a*k**2)*E))
zz = eigvals(A)
z1.append(zz[0])
z2.append(zz[1])
z1 = array(z1)
z2 = array(z2)
figure(1)
plot(karr,real(z1))
plot(karr,real(z2))
xlabel('k')
ylabel('Re(z)')
grid()
figure(2)
plot(karr,imag(z1))
plot(karr,imag(z2))
xlabel('k')
ylabel('Im(z)')
#figure(3)
#plot(real(z1),imag(z1))
#plot(real(z2),imag(z2))
#xlabel('Re(z)')
#ylabel('Im(z)')
grid()
show()
def main():
# DATI
a = 3
Omega = 0.8
O2 = Omega**2
xie = 0.1
xig = 0.5
ra = sqrt(0.25)
Nelem = 119
NWake = (Nelem + 1) // 2 * 10
rt = 0.1
M = array([[1, xig], [xig, ra**2 + 2 * xig * xie - xie**2]])
K = array([[O2, O2 * xie], [O2 * xie, ra**2 + O2 * xie**2]])
I = complex(0, 1)
karr = linspace(0.2, 1, 100)
z1 = []
z2 = []
kg = []
for k in karr:
E = ematrixwing(Nelem, NWake, rt, I * k) / (2. * pi)
#print E
A = -dot(inv(K), (M + 1. / (a * k**2) * E))
zz = eigvals(A)
z1.append(zz[0])
z2.append(zz[1])
z1 = array(z1)
z2 = array(z2)
figure(1)
plot(karr, real(z1))
plot(karr, real(z2))
xlabel('k')
ylabel('Re(z)')
grid()
figure(2)
plot(karr, imag(z1))
plot(karr, imag(z2))
xlabel('k')
ylabel('Im(z)')
#figure(3)
#plot(real(z1),imag(z1))
#plot(real(z2),imag(z2))
#xlabel('Re(z)')
#ylabel('Im(z)')
grid()
show()
def Elong(Nelem, NWake, rt, parr):
E = []
for p in parr:
E.extend(ematrixwing(Nelem, NWake, rt, p).ravel().tolist())
return E
def Elong(Nelem,NWake,rt,parr):
E = []
for p in parr:
E.extend(ematrixwing(Nelem, NWake, rt, p).ravel().tolist())
return E
