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mirror of https://github.com/TREX-CoE/irpjast.git synced 2024-12-24 21:34:04 +01:00
irpjast/jastlib.py
2021-03-10 14:04:07 +01:00

272 lines
8.1 KiB
Python

import numpy as np
import matplotlib.pyplot as plt
def get_sphere_distribution(n, dmin, Ls, maxiter=1e4, allow_wall=True):
"""Get random points in a box with given dimensions and minimum separation.
Parameters:
- n: number of points
- dmin: minimum distance
- Ls: dimensions of box, shape (3,) array
- maxiter: maximum number of iterations.
- allow_wall: whether to allow points on wall;
(if False: points need to keep distance dmin/2 from the walls.)
Return:
- ps: array (n, 3) of point positions,
with 0 <= ps[:, i] < Ls[i]
- n_iter: number of iterations
- dratio: average nearest-neighbor distance, divided by dmin.
Note: with a fill density (sphere volume divided by box volume) above about
0.53, it takes very long. (Random close-packed spheres have a fill density
of 0.64).
Author: Han-Kwang Nienhuys (2020)
Copying: BSD, GPL, LGPL, CC-BY, CC-BY-SA
See Stackoverflow: https://stackoverflow.com/a/62895898/6228891
"""
Ls = np.array(Ls).reshape(3)
if not allow_wall:
Ls -= dmin
# filling factor; 0.64 is for random close-packed spheres
# This is an estimate because close packing is complicated near the walls.
# It doesn't work well for small L/dmin ratios.
sphere_vol = np.pi/6*dmin**3
box_vol = np.prod(Ls + 0.5*dmin)
fill_dens = n*sphere_vol/box_vol
if fill_dens > 0.64:
msg = f'Too many to fit in the volume, density {fill_dens:.3g}>0.64'
raise ValueError(msg)
# initial try
ps = np.random.uniform(size=(n, 3)) * Ls
# distance-squared matrix (diagonal is self-distance, don't count)
dsq = ((ps - ps.reshape(n, 1, 3))**2).sum(axis=2)
dsq[np.arange(n), np.arange(n)] = np.infty
for iter_no in range(int(maxiter)):
# find points that have too close neighbors
close_counts = np.sum(dsq < dmin**2, axis=1) # shape (n,)
n_close = np.count_nonzero(close_counts)
if n_close == 0:
break
# Move the one with the largest number of too-close neighbors
imv = np.argmax(close_counts)
# new positions
newp = np.random.uniform(size=3)*Ls
ps[imv]= newp
# update distance matrix
new_dsq_row = ((ps - newp.reshape(1, 3))**2).sum(axis=-1)
dsq[imv, :] = dsq[:, imv] = new_dsq_row
dsq[imv, imv] = np.inf
else:
raise RuntimeError(f'Failed after {iter_no+1} iterations.')
if not allow_wall:
ps += dmin/2
dratio = (np.sqrt(dsq.min(axis=1))/dmin).mean()
return ps, iter_no+1, dratio
def generateElsAroundPoints(n,LS,dmin):
"""
Parameters:
- n: number of points
- LS: list of position of all atoms
- dmin: minimum intra block distance
- shift: inter block distance
Return:
- r: array (n, 3) of point positions,
"""
xs = None
for Ls in LS:
# Get list of random points around Ls
distrib,a,b = get_sphere_distribution(n,dmin,Ls)
if xs is None:
xs = distrib[:,0]
ys = distrib[:,1]
zs = distrib[:,2]
else:
xs = np.concatenate((xs,distrib[:,0]))
ys = np.concatenate((ys,distrib[:,1]))
zs = np.concatenate((zs,distrib[:,2]))
return((np.array((xs,ys,zs))).T)
def getCoefList(Nord,Natom):
assert(Nord < 11)
dict = {
0 : lambda x,y:x-y-2,
1 : lambda x,y:x-y,
2 : lambda x,y:x-y,
3 : lambda x,y:x-y,
4 : lambda x,y:x-y,
5 : lambda x,y:x-y,
6 : lambda x,y:x-y,
7 : lambda x,y:x-y,
8 : lambda x,y:x-y,
9 : lambda x,y:x-y,
10 : lambda x,y:x-y,
11 : lambda x,y:x-y,
}
count = 0
for p in range(2,Nord+1):
for k in range(p-1,-1,-1):
lmax = dict[k](p,k)
for l in range(lmax,-1,-1):
if (p-k-l) & 1 is 0:
count += 1
coeflista = np.random.rand(Nord+1,Natom)
coeflistb = np.random.rand(Nord+1)
coeflistc = np.random.rand(count,Natom)
return (coeflista.reshape((Nord+1)*Natom),coeflistb,coeflistc.reshape(count*Natom))
#return (coeflista,coeflistb,coeflistc)
def get_sphere_distribution(n, dmin, Ls, maxiter=1e4, allow_wall=True):
"""Get random points in a box with given dimensions and minimum separation.
Parameters:
- n: number of points
- dmin: minimum distance
- Ls: dimensions of box, shape (3,) array
- maxiter: maximum number of iterations.
- allow_wall: whether to allow points on wall;
(if False: points need to keep distance dmin/2 from the walls.)
Return:
- ps: array (n, 3) of point positions,
with 0 <= ps[:, i] < Ls[i]
- n_iter: number of iterations
- dratio: average nearest-neighbor distance, divided by dmin.
Note: with a fill density (sphere volume divided by box volume) above about
0.53, it takes very long. (Random close-packed spheres have a fill density
of 0.64).
Author: Han-Kwang Nienhuys (2020)
Copying: BSD, GPL, LGPL, CC-BY, CC-BY-SA
See Stackoverflow: https://stackoverflow.com/a/62895898/6228891
"""
Ls = np.array(Ls).reshape(3)
if not allow_wall:
Ls -= dmin
# filling factor; 0.64 is for random close-packed spheres
# This is an estimate because close packing is complicated near the walls.
# It doesn't work well for small L/dmin ratios.
sphere_vol = np.pi/6*dmin**3
box_vol = np.prod(Ls + 0.5*dmin)
fill_dens = n*sphere_vol/box_vol
if fill_dens > 0.64:
msg = f'Too many to fit in the volume, density {fill_dens:.3g}>0.64'
raise ValueError(msg)
# initial try
ps = np.random.uniform(size=(n, 3)) * Ls
# distance-squared matrix (diagonal is self-distance, don't count)
dsq = ((ps - ps.reshape(n, 1, 3))**2).sum(axis=2)
dsq[np.arange(n), np.arange(n)] = np.infty
for iter_no in range(int(maxiter)):
# find points that have too close neighbors
close_counts = np.sum(dsq < dmin**2, axis=1) # shape (n,)
n_close = np.count_nonzero(close_counts)
if n_close == 0:
break
# Move the one with the largest number of too-close neighbors
imv = np.argmax(close_counts)
# new positions
newp = np.random.uniform(size=3)*Ls
ps[imv]= newp
# update distance matrix
new_dsq_row = ((ps - newp.reshape(1, 3))**2).sum(axis=-1)
dsq[imv, :] = dsq[:, imv] = new_dsq_row
dsq[imv, imv] = np.inf
else:
raise RuntimeError(f'Failed after {iter_no+1} iterations.')
if not allow_wall:
ps += dmin/2
dratio = (np.sqrt(dsq.min(axis=1))/dmin).mean()
return ps, iter_no+1, dratio
def scalingee(r,kappa=1.0):
return (numpy.ones_like(r) - numpy.exp(-kappa*r))/kappa
def scalingen(r,kappa=1.0):
return numpy.exp(-kappa*r)
if False:
Nord = 5
L1 = 2.0
n = 2 # number of points
dmin = 0.1 # min dist between points
Ls = np.array([L1,L1,L1]) # lengths of the box
shift = -10.0
kappa = 2.0
filename_atom = str(n) + "_geometry.txt"
filename_elec = str(n)
filename_coeffs = str(n) + "_jast_coeffs.txt"
(coeffsa, coeffsb, coeffsc) = getCoefList(Nord,n)
coeffsall = np.concatenate((coeffsa,coeffsb,coeffsc))
print(coeffsa.shape,coeffsb.shape,coeffsc.shape)
atomList,_,_ = get_sphere_distribution(n, dmin, Ls, maxiter=1e4, allow_wall=True)
#print(atomList)
L1 = 5.0
n = 5 # number of points
dmin = 0.1 # min dist between points
Ls = np.array([L1,L1,L1]) # lengths of the box
shift = -10.0
kappa = 2.0
filename_elec = filename_elec + "_" + str(n) + "_elec_coord.txt"
#rlist = generateBlockRandomPointsAtShftApart(n,L1,dmin,shift)
rlist = generateElsAroundPoints(n,atomList,dmin)
# Save file
np.savetxt(filename_elec,rlist)
np.savetxt(filename_atom,atomList)
np.savetxt(filename_coeffs,coeffsall)
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
xs = rlist.T[0]
ys = rlist.T[1]
zs = rlist.T[2]
ax.scatter(xs, ys, zs, marker='o')
plt.show()
rijScaled = np.array([[(lambda xval, yval: np.linalg.norm(xval-yval))(xval,yval) for yval in rlist] for xval in rlist])
plt.imshow(rijScaled)
plt.colorbar()
plt.show()