Example #1
0
    def create_basinhopping(self, add_minimum=None, potential=None):
        if (potential is None):
            potential = self.create_potential()

        coords = self.initial_coords()
        step = self.create_takestep()

        opts = self.options

        print "Initial energy ", potential.getEnergy(coords)
        print "Creating basin hopping with quencher"
        print "------------------------------------"
        print self.quenchRoutine
        for key, value in self.quenchParameters.iteritems():
            print key, "=", value
        print "------------------------------------"

        if self.target_energy is not None:
            add_minimum = self.check_converged

        if (add_minimum is None):
            add_minimum = self.database.minimum_adder()

        return BasinHopping(coords,
                            potential,
                            takeStep=step,
                            temperature=opts.temperature,
                            storage=add_minimum,
                            quenchRoutine=self.quenchRoutine,
                            quenchParameters=self.quenchParameters)
Example #2
0
    def minimize(self):
        #shape(visits2d) is now (nqbins, nebins, nreps)
        #we need it to be (nreps, nqbins*nebins)
        #first reorder indices
        nreps = self.nrep
        nebins = self.nebins
        nqbins = self.nqbins
        nbins = self.nebins * self.nqbins
        #visits = np.zeros([nreps, nebins, nqbins], np.integer)
        reduced_energy = np.zeros([nreps, nebins, nqbins])
#        for k in range(self.nrep):
#            for j in range(self.nqbins):
#                for i in range(self.nebins):
#                    #visits[k,i,j] = self.visits2d[i,j,k]
#                    reduced_energy[k,i,j] = self.binenergy[i] / (self.Tlist[k]*self.k_B)
        for j in range(self.nqbins):
            reduced_energy[:,:,j] = self.binenergy[np.newaxis,:] / (self.Tlist[:,np.newaxis]*self.k_B)
                    
        visits = self.visits2d
        visits = np.reshape( visits, [nreps, nbins ]) 
        reduced_energy = np.reshape( reduced_energy, [nreps, nbins])           
        self.logP = np.where( visits != 0, np.log( visits.astype(float) ), 0 )

        
        from wham_potential import WhamPotential
        whampot = WhamPotential( self.logP, reduced_energy )
        
        nvar = nbins + nreps
        X = np.random.rand(nvar)
        print "initial energy", whampot.getEnergy(X)
        try: 
            from pygmin.optimize import mylbfgs as quench
            ret = quench(X, whampot, iprint=10, maxstep = 1e4)
        except ImportError:
            from pygmin.optimize import lbfgs_scipy as quench
            ret = quench(X, whampot)            

        print "quenched energy", ret.energy
        
        global_min = False
        if global_min:
            from pygmin.basinhopping import BasinHopping
            from pygmin.takestep.displace import RandomDisplacement
            takestep = RandomDisplacement(stepsize=10.)
            takestep.useAdaptiveStep()
            takestep.adaptive_class.f = 2.
            bh = BasinHopping(X, whampot, takestep)
            bh.run(1000)
        
        
        #self.logn_Eq = zeros([nebins,nqbins], float64)
        X = ret.coords
        self.logn_Eq = X[nreps:]
        self.w_i_final = X[:nreps]
        
        self.logn_Eq = np.reshape(self.logn_Eq, [nebins, nqbins])
        self.logn_Eq = np.where( self.visits2d.sum(0) == 0, self.LOGMIN, self.logn_Eq )
Example #3
0
def test_basin_hopping(pot, angles):
    from pygmin.basinhopping import BasinHopping
    from pygmin.takestep.displace import RandomDisplacement
    from pygmin.takestep.adaptive import AdaptiveStepsize

    takestep = RandomDisplacement(stepsize=np.pi / 4)
    takestepa = AdaptiveStepsize(takestep, frequency=20)

    bh = BasinHopping(angles, pot, takestepa, temperature=1.01)
    bh.run(20)
Example #4
0
def getInitialCoords(natoms, pot):
    from pygmin.basinhopping import BasinHopping
    from pygmin.takestep.displace import RandomDisplacement
    takestep = RandomDisplacement(0.3)
    X = np.random.uniform(-1, 1, natoms * 3) * (1. * natoms)**(1. / 3) * .1
    bh = BasinHopping(X, pot, takestep)
    bh.run(30)

    X = bh.coords
    return X
Example #5
0
def getSetOfMinLJ(natoms = 11): #for testing purposes
    from pygmin.potentials.lj import LJ
    pot = LJ()
    coords = np.random.uniform(-1,1,natoms*3)
    from pygmin.basinhopping import BasinHopping
    from pygmin.takestep.displace import RandomDisplacement
    from pygmin.takestep.adaptive import AdaptiveStepsize
    from pygmin.storage.savenlowest import SaveN
    saveit = SaveN(10)
    takestep1 = RandomDisplacement()
    takestep = AdaptiveStepsize(takestep1, frequency=15)
    bh = BasinHopping(coords, pot, takestep, storage=saveit, outstream=None)
    bh.run(100)
    return pot, saveit
def guesstsLJ():
    from pygmin.potentials.lj import LJ
    pot = LJ()
    natoms = 9
    coords = np.random.uniform(-1, 1, natoms * 3)
    from pygmin.basinhopping import BasinHopping
    from pygmin.takestep.displace import RandomDisplacement
    from pygmin.takestep.adaptive import AdaptiveStepsize
    from pygmin.storage.savenlowest import SaveN
    saveit = SaveN(10)
    takestep1 = RandomDisplacement()
    takestep = AdaptiveStepsize(takestep1, frequency=15)
    bh = BasinHopping(coords, pot, takestep, storage=saveit, outstream=None)
    bh.run(100)
    coords1 = saveit.data[0].coords
    coords2 = saveit.data[1].coords

    return guessts(coords1, coords2, pot)
Example #7
0
    def globalMinimization(self):
        """
        in experimentation i've never been able to find more than
        one minimum
        """
        nreps = self.nrep
        nbins = self.nebins
        visitsT = (self.visits1d)
        #print "min vis", np.min(visitsT)
        self.logP = np.where(visitsT != 0, np.log(visitsT), 0)
        #print "minlogp", np.min(self.logP)
        self.reduced_energy = self.binenergy[np.newaxis, :] / (
            self.Tlist[:, np.newaxis] * self.k_B)

        self.whampot = WhamPotential(self.logP, self.reduced_energy)

        X = np.random.rand(nreps + nbins)
        E = self.whampot.getEnergy(X)
        print "energy", E

        print "quenching"
        from pygmin.optimize import lbfgs_scipy as quench
        ret = quench(X, self.whampot)
        print "quench energy", ret.energy

        from pygmin.basinhopping import BasinHopping
        from pygmin.takestep.displace import RandomDisplacement
        takestep = RandomDisplacement(stepsize=10)
        takestep.useAdaptiveStep()
        takestep.adaptive_class.f = 1.5  #i have no idea what a good stepsize should be
        bh = BasinHopping(X, self.whampot, takestep)

        import matplotlib.pyplot as plt
        for i in range(10):
            bh.run(2000)
            self.logn_E = bh.coords[nreps:]
            cvdata = self.calc_Cv(400)
            plt.plot(cvdata[:, 0], cvdata[:, 5], '-')
        plt.show()

        X = bh.coords
        self.logn_E = X[nreps:]
        self.w_i_final = X[:nreps]
Example #8
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

takestep = RandomDisplacement(stepsize=np.pi / 4)
takestepa = AdaptiveStepsize(takestep, frequency=10)
storage = savenlowest.SaveN(20)

bh = BasinHopping(coords, pot, takestepa, temperature=1.01, storage=storage)
bh.run(200)

print "lowest structures fount:"
with open("out.spins", "w") as fout:
    for min in storage.data:
        m = getm(min.coords)
        print "energy", min.energy, "magnetization", m
        fout.write("energy %g magnetization %g\n" % (min.energy, m))
        printspins(fout, pot, min.coords)
        fout.write("\n\n")
"""
view the spins with gnuplot using the command
h = 2.
s = 0.7
splot 'out.spins' u 1:2:(0) w p pt 5, '' index 1 u 1:2:(0):($6/h):($7/h):($8/h) w vectors t "fields", '' index 1 u 1:2:(0):($3*s):($4*s):($5*s) w vectors t "spins"
Example #9
0
coords = np.zeros(2 * 3 * nmol, np.float64)
coords[0:nmol *
       3] = np.random.uniform(-1, 1, [nmol * 3]) * 1.3 * (nsites)**(1. / 3)
for i in range(nmol):
    k = nmol * 3 + 3 * i
    coords[k:k + 3] = rot.random_aa()

#set up the takestep routine
from pygmin.potentials.rigid_bodies.take_step import RBTakeStep
takestep = RBTakeStep()

#set up the class to save lowest energy structures
from pygmin.storage.savenlowest import SaveN
saveit = SaveN(100)

#set up basinhopping
from pygmin.basinhopping import BasinHopping
bh = BasinHopping(coords, mysys, takestep, storage=saveit.insert)

#run basin hopping
bh.run(40)

#print the saved coords
fname = "otp.xyz"
print "saving xyz coords to", fname
from pygmin.printing.print_atoms_xyz import printAtomsXYZ as printxyz
with open(fname, "w") as fout:
    for minimum in saveit.data:
        xyz = mysys.getxyz(minimum.coords)
        printxyz(fout, xyz, atom_type=["N", "O", "O"])
Example #10
0
                                                rotate=0.),
                                  frequency=50)
step2 = takestep.AdaptiveStepsize(OXDNATakestep(displace=0.,
                                                rotate=parameters.rotate),
                                  frequency=50)
group.addBlock(100, step1)
group.addBlock(100, step2)
# with a generate random configuration
genrandom = OXDNAReseed()
# in a reseeding takestep procedure
reseed = takestep.Reseeding(group, genrandom, maxnoimprove=parameters.reseed)

# store all minima in a database
db = Database(db="storage.sqlite", accuracy=1e-2)

# create Basinhopping object
opt = BasinHopping(coords,
                   potential,
                   reseed,
                   db.minimum_adder(),
                   temperature=parameters.temperature)

# run for 100 steps
opt.run(parameters.nsteps)

# now dump all the minima
i = 0
for m in db.minima():
    i += 1
    GMIN.userpot_dump("lowest_%03d.dat" % (i), m.coords)