e = tt.matrix(e,1e-12)
#Generate ssx, ssz
ssp = [gen_1d(sp,e,i,d) for i in xrange(d)]
ssz = [gen_1d(sz,e,i,d) for i in xrange(d)]
ssm = [gen_1d(sm,e,i,d) for i in xrange(d)]
A = None
for i in xrange(d-1):
A = A + 0.5 * (ssp[i] * ssm[i+1] + ssm[i] * ssp[i+1]) + (ssz[i] * ssz[i+1])
A = A.round(1e-8)
return A
if __name__ == '__main__':
d = 20 #The dimension of the problem (number of spins)
B = 3 # Number of eigenvalues sought
eps = 1e-6 #Accuracy of the computations
A = gen_heisen(d)
n = A.n
d = A.tt.d
r = [2]*(d+1)
r[0] = 1
r[d] = B
x0 = tt.rand(n,d,r)
t1 = time.time()
print 'Matrices are done'
y, lam = eigb(A, x0, eps)
t2 = time.time()
print 'Elapsed time: %3.1f' % (t2 - t1)
print 'Eigenvalues:', lam
e = tt.matrix(e,1e-12)
#Generate ssx, ssz
ssp = [gen_1d(sp,e,i,d) for i in xrange(d)]
ssz = [gen_1d(sz,e,i,d) for i in xrange(d)]
ssm = [gen_1d(sm,e,i,d) for i in xrange(d)]
A = None
for i in xrange(d-1):
A = A + 0.5 * (ssp[i] * ssm[i+1] + ssm[i] * ssp[i+1]) + (ssz[i] * ssz[i+1])
A = A.round(1e-8)
return A
if __name__ == '__main__':
d = 60 #The dimension of the problem (number of spins)
B = 5 # Number of eigenvalues sought
eps = 1e-5 #Accuracy of the computations
A = gen_heisen(d)
n = A.n
d = A.tt.d
r = [B]*(d+1)
r[0] = 1
r[d] = B
x0 = tt.rand(n,d,r)
t1 = time.time()
print('Matrices are done')
y, lam = eigb(A, x0, eps, max_full_size = 1000)
t2 = time.time()
print('Elapsed time: %3.1f' % (t2 - t1))
print('Eigenvalues: ', lam)
sp = tt.matrix(sp,1e-12)
sm = tt.matrix(sm,1e-12)
e = tt.matrix(e,1e-12)
#Generate ssx, ssz
ssp = [gen_1d(sp,e,i,d) for i in xrange(d)]
ssz = [gen_1d(sz,e,i,d) for i in xrange(d)]
ssm = [gen_1d(sm,e,i,d) for i in xrange(d)]
A = None
for i in xrange(d-1):
A = A + 0.5 * (ssp[i] * ssm[i+1] + ssm[i] * ssp[i+1]) + (ssz[i] * ssz[i+1])
A = A.round(1e-8)
return A
es = []
lm = []
ds = [20]
for d in ds:
B = 3
A = gen_heisen(d)
n = A.n
d = A.tt.d
r = [2]*(d+1)
r[0] = 1
r[d] = B
x0 = tt.rand(n,d,r)
t1 = time.time()
print 'Matrices are done'
y, lam = eigb(A,x0,1e-3)
es.append(lam[0]/d)
lm.append(d)
t2 = time.time()
