Exemplo n.º 1
0
def test():
    pi = np.pi
    L = 3
    nspins = L**2
    
    #phases = np.zeros(nspins)
    pot = XYModel( dim = [L,L], phi = np.pi) #, phases=phases)
    
    
    angles = np.random.uniform(-pi, pi, nspins)
    print angles

    e = pot.getEnergy(angles)
    print "energy ", e

    print "numerical gradient"
    ret = pot.getEnergyGradientNumerical(angles)
    print ret[1]
    print "analytical gradient"
    ret2 = pot.getEnergyGradient(angles)
    print ret2[1]
    print ret[0]
    print ret2[0]
    

    
    #try a quench
    from pygmin.optimize.quench import mylbfgs
    ret = mylbfgs(angles, pot.getEnergyGradient)
    
    print "quenched e = ", ret[1]
    print ret[0]
    
    test_basin_hopping(pot, angles)
Exemplo n.º 2
0
def test():
    pi = np.pi
    L = 4
    nspins = L**2
    
    #phases = np.zeros(nspins)
    pot = HeisenbergModelRA( dim = [L,L], field_disorder = 2. ) #, phases=phases)
    
    coords = np.zeros([nspins, 2])
    for i in range(nspins): 
        vec = rotations.vec_random()
        coords[i,:] = make2dVector(vec)
    coords = np.reshape(coords, [nspins*2])
    if False:
        normfields = np.copy(pot.fields)
        for i in range(nspins): normfields[i,:] /= np.linalg.norm(normfields[i,:])
        coords = coords3ToCoords2( np.reshape(normfields, [nspins*3] ) )
        coords  = np.reshape(coords, nspins*2)
    #print np.shape(coords)
    coordsinit = np.copy(coords)
    
    #print "fields", pot.fields
    print coords
    
    if False:
        coords3 = coords2ToCoords3(coords)
        coords2 = coords3ToCoords2(coords3)
        print np.reshape(coords, [nspins,2])
        print coords2
        coords3new = coords2ToCoords3(coords2)
        print coords3
        print coords3new

    e = pot.getEnergy(coords)
    print "energy ", e
    if True:
        print "numerical gradient"
        ret = pot.getEnergyGradientNumerical(coords)
        print ret[1]
        if True:
            print "analytical gradient"
            ret2 = pot.getEnergyGradient(coords)
            print ret2[1]
            print ret[0]
            print ret2[0]
            #print "ratio"
            #print ret2[1] / ret[1]
            #print "inverse sin"
            #print 1./sin(coords)
            #print cos(coords)
    
    print "try a quench"
    from pygmin.optimize.quench import mylbfgs
    ret = mylbfgs(coords, pot.getEnergyGradient)
    
    print "quenched e = ", ret[1], "funcalls", ret[3]
    print ret[0]
    with open("out.spins", "w") as fout:
        s = coords2ToCoords3( ret[0] )
        h = pot.fields
        c = coords2ToCoords3( coordsinit )
        for node in pot.G.nodes():
            i = pot.indices[node]
            fout.write( "%g %g %g %g %g %g %g %g %g %g %g\n" % (node[0], node[1], \
                s[i,0], s[i,1], s[i,2], h[i,0], h[i,1], h[i,2], c[i,0], c[i,1], c[i,2] ) )
    
    coords3 = coords2ToCoords3( ret[0] )
    m = np.linalg.norm( coords3.sum(0) ) / nspins
    print "magnetization after quench", m
    
    test_basin_hopping(pot, coords)
Exemplo n.º 3
0
                  help="outfile for results")

(options, args) = parser.parse_args()

configurations = pickle.load(open("quench_benchmark.dat"))

GMIN.initialize()
pot = GMINPotential(GMIN)

#fl = open("quenched.xyz", "w")
res = open("results.txt", "w")

t0 = time.time()
print "# energy nsteps rms"
res.write("# energy nsteps rms\n")
for coords in configurations[0:5]:
    ret = mylbfgs(coords,
                  pot.getEnergyGradient,
                  tol=options.tol,
                  M=options.M,
                  maxstep=options.maxstep,
                  maxErise=options.maxErise)
    energy = ret[1]
    fcalls = ret[3]
    #oxdna.export_xyz(fl, ret[0])
    print energy, fcalls, ret[2]
    res.write("%f %d %g\n" % (energy, fcalls, ret[2]))

print "total runtime: ", time.time() - t0
#fl.close()
res.close()
Exemplo n.º 4
0
parser.add_option("--maxErise", dest="maxErise", type=float, default=1e-4,
                  help="maximum energy increase for lbfgs")
parser.add_option("--maxstep", dest="maxstep", type=float, default=0.1,
                  help="maximum stepsize for minimizer")
parser.add_option("-o", dest="outfile", default="results.txt",
                  help="outfile for results")

(options, args) = parser.parse_args()

configurations = pickle.load(open("quench_benchmark.dat"))

GMIN.initialize()
pot = GMINPotential(GMIN)

#fl = open("quenched.xyz", "w")
res = open("results.txt", "w")

t0 = time.time()
print "# energy nsteps rms" 
res.write("# energy nsteps rms\n")
for coords in configurations[0:5]:
    ret = mylbfgs(coords, pot.getEnergyGradient, tol=options.tol, M=options.M, maxstep=options.maxstep, maxErise=options.maxErise)
    energy = ret[1]
    fcalls = ret[3]
    #oxdna.export_xyz(fl, ret[0])
    print energy, fcalls, ret[2]
    res.write("%f %d %g\n"%(energy, fcalls, ret[2]))
              
print "total runtime: ", time.time()-t0
#fl.close()
res.close()
Exemplo n.º 5
0
    vec = rotations.vec_random()
    coords[i,:] = make2dVector(vec)
coords = np.reshape(coords, [nspins*2])
#print np.shape(coords)
coordsinit = np.copy(coords)

#print "fields", pot.fields
print coords


e = pot.getEnergy(coords)
print "energy ", e

print "try a quench"
from pygmin.optimize.quench import mylbfgs
ret = mylbfgs(coords, pot.getEnergyGradient)

print "quenched e = ", ret[1], "funcalls", ret[3]
print ret[0]

m = getm( ret[0] )
print "magnetization after quench", m


#do basin hopping

from pygmin.basinhopping import BasinHopping
from pygmin.takestep.displace import RandomDisplacement
from pygmin.takestep.adaptive import AdaptiveStepsize
from pygmin.storage import savenlowest
Exemplo n.º 6
0
#phases = np.zeros(nspins)
pot = XYModel( dim = [L,L], phi = np.pi) #, phases=phases)


angles = np.random.uniform(-pi, pi, nspins)
print angles

e = pot.getEnergy(angles)
print "energy ", e



#try a quench
if False:
    from pygmin.optimize.quench import mylbfgs
    ret = mylbfgs(angles, pot.getEnergyGradient)
    
    print "quenched e = ", ret[1]
    print ret[0]


#set up and run basin hopping

from pygmin.basinhopping import BasinHopping
from pygmin.takestep.displace import RandomDisplacement
from pygmin.takestep.adaptive import AdaptiveStepsize
from pygmin.storage import savenlowest

#should probably use a different take step routine  which takes into account
#the cyclical periodicity of angles
takestep = RandomDisplacement(stepsize = np.pi/4)