def build_operators(spos, trans, check_mapping=False, eps=1e-6):
'''Given a list of fractional positions, and a list of
fractional translations, produce a set of matrices,
describing how fractional translations permute atomic
positions within the unit cell. Two fractional positions
si and sj are considered to be identical when |si-sj|<eps.
'''
ntrans = len(trans)
natoms = len(spos)
ops = np.zeros((ntrans, natoms, natoms), int)
for i, ti in enumerate(trans):
for j, sj in enumerate(spos):
for k, sk in enumerate(spos):
# If displacement between two atomic positions
# differs from the fractional translations by
# by a lattice translation+-eps we consider the
# that two atomic positions to be map onto each
# other by the fractional translation
disp = sk - sj - ti
ops[i, j, k] = np.linalg.norm(disp - np.rint(disp)) < eps
if check_mapping:
# Every row and every column of every operator must
# contain exactly one unity, otherwise translations
# are not maping atoms one-to-one.
if np.any(np.sum(ops, axis=1) != 1) or np.any(
np.sum(ops, axis=2) != 1):
post_error('Translations are not one-to-one. '
'Try changing the matching tolerance, or try using '
'the POSCAR file with more regular positions.')
return ops
def build_operators(spos, trans, check_mapping=False, eps=1e-6):
"""Given a list of fractional positions, and a list of
fractional translations, produce a set of matrices,
describing how fractional translations permute atomic
positions within the unit cell. Two fractional positions
si and sj are considered to be identical when |si-sj|<eps.
"""
ntrans = len(trans)
natoms = len(spos)
ops = np.zeros((ntrans, natoms, natoms), int)
for i, ti in enumerate(trans):
for j, sj in enumerate(spos):
for k, sk in enumerate(spos):
# If displacement between two atomic positions
# differs from the fractional translations by
# by a lattice translation+-eps we consider the
# that two atomic positions to be map onto each
# other by the fractional translation
disp = sk - sj - ti
ops[i, j, k] = np.linalg.norm(disp - np.rint(disp)) < eps
if check_mapping:
# Every row and every column of every operator must
# contain exactly one unity, otherwise translations
# are not maping atoms one-to-one.
if np.any(np.sum(ops, axis=1) != 1) or np.any(np.sum(ops, axis=2) != 1):
post_error(
"Translations are not one-to-one. "
"Try changing the matching tolerance, or try using "
"the POSCAR file with more regular positions."
)
return ops
def parse_poscar(filename):
'''Parses POSCAR file. Returns 3x3 float array
containing unit cell vectors as rows, Nx3
array containing fractional positions of atoms,
N being number of atoms and a list of chemical
symbols.
'''
try:
gl = Getlines(filename)
except:
post_error('Unable to open "{0}" for reading.'.format(filename))
# Skip the comment line
gl.get_next()
# Read the scaling factor
f = float(gl.get_next())
# Read the unit cell vectors
cell = np.zeros((3, 3), float)
cell[0] = f * np.array(gl.get_next().split(), float)
cell[1] = f * np.array(gl.get_next().split(), float)
cell[2] = f * np.array(gl.get_next().split(), float)
# Read the chemical symbols
syms = gl.get_next().split()
# Read the atom counts
counts = np.array(gl.get_next().split(), int)
# Get the number of atoms
natoms = np.sum(counts)
# Rearrange into the long list of chemical symbols
symbols = []
for s, c in zip(syms, counts):
symbols += [s] * c
# Cartesian or fractional coordinates?
ctype = gl.get_next()[0].lower()
if ctype == 'c':
mult = np.linalg.inv(cell)
elif ctype == 'd':
mult = np.eye(3)
else:
post_error('"{0}" is unknown POSCAR option'.format(plines[7].strip()))
# Allocate storage for positions
spos = np.zeros((len(symbols), 3))
# Read the positions
for i in xrange(len(symbols)):
spos[i] = np.array(gl.get_next().split()[:3], float)
return cell, spos, symbols
def main():
desc_str = 'Unfold bands calculated by VASP. For this, phase '\
'information needs to be present in the PROCAR file '\
'which means that bands need to be calculated with '\
'the option LORBIT=12 specified in the INCAR file. '\
'The required input consists of POSCAR file, PROCAR '\
'file and a set of up to three fractional translations. '\
'There is no need to specify all translations, just the '\
'generators. The programs will generate all distinct '\
'translations from the generators and generate all irreps. '\
'NOTE: In cas of non-collinear spin-polarized calculations ' \
'mx, my and mz components of orbital weights are not ' \
'unfolded, only spin up and spin down totals.'
parser = argparse.ArgumentParser(prog='vasp_unfold', description = desc_str)
parser.add_argument('poscar', type=str, help='POSCAR file')
parser.add_argument('procar', type=str, help='PROCAR file')
parser.add_argument('--tgen', type=translation, action='append',
metavar='SX,SY,SZ', help='Fractional translation '
'generator. No whitespaces are allowed between the '
'components! SX, SY and SZ can be either 0 or 1/n, '
'where n is an integer. Up to three linearly '
'independant generators can be specified.')
parser.add_argument('--out', type=str, help='Output filename. If left '
'unspecified output is writen to PROCAR.irrep.n '
'where PROCAR is location of the input PROCAR file. '
'If specified, output is written to OUT.irrep.n.')
parser.add_argument('--eps', type=float, default=1e-6, help='Numerical '
'precision. When building permutation representation '
'of the fractional translations this parameter is used '
'to determine whether two fractional positions are '
'identical. For irregular structures, it may need to '
'be increased. If this does not help, try to tweak '
'the atomic positions in POSCAR to make the structure '
'more regular. Default is 1e-6.')
parser.add_argument('--all-irreps', default=False, action='store_true',
help='Flag specifying that all irreps from the unfolding '
'will be written to the output. By default, only irrep 0 '
'(unit irrep) is written out.')
parser.add_argument('--check-mapping', action='store_true', default=False,
help='Specifies to check if supplied translation '
'generators generate fractional translations which are '
'one-to-one, ie. map every atom on exactly one other atom '
'in the unit cell. This MUST not be enabled for the cases '
'where vacancies or excess atoms are present.')
args = parser.parse_args()
tgens = args.tgen
trans, irreps = build_translations(tgens)
try:
cell, spos, symbols = parse_poscar(args.poscar)
except:
post_error('Unable to parse the input POSCAR file. Please '
'check if the file exists and is formatted properly')
ops = build_operators(spos, trans, args.check_mapping, args.eps)
try:
data = parse_procar(args.procar)
except:
post_error(errors.poscar_parse_error)
if data[-1] is None:
post_error('Phase information has to be present in the PROCAR '
'file. Please repeat the calculation with LORBIT=12.')
phases = np.copy(data[-1])
norbs = phases.shape[1]/len(spos)
projs = build_projectors(irreps, ops, norbs)
if args.out is None:
output = args.procar
else:
output = args.out
if args.all_irreps:
nirrep = len(projs)
else:
nirrep = 1
for i, p in enumerate(projs[:nirrep]):
for s in xrange(data[-1].shape[-1]):
try:
data[-1][:,:,:,s] = np.dot(p, phases[:,:,:,s]).swapaxes(0, 1)
except:
post_error('Unable to apply projectors. Are you sure '
'that specified POSCAR and PROCAR file belong to '
'the same crystal structure?')
# We update total absolute weights to correspond to
# unfolded phases (by multiplying them by the magnitude
# ratio of unfolded and folded phases
phase_ratio = np.abs(data[-1])/(np.abs(phases)+1e-4)
for idim in xrange(data[-2].shape[3]):
data[-2][:,:,:,idim,:] *= phase_ratio
write_procar('{0}.irrep.{1}'.format(output, i), *data)
def write_procar(fname, orbitals, kpoints, kweights, bands,
occupations, weights, phases):
'''Write PROCAR file based on supplied data
'''
# Labels for orbitals
orblabels = ['s', 'py', 'pz', 'px', 'dxy', 'dyz', 'dz2', 'dxz', 'dx2',
'f-3', 'f-2', 'f-1', 'f0', 'f1', 'f2', 'f3']
norb = len(orbitals)
npoints = len(kpoints)
nbands = bands.shape[1]
nions = weights.shape[1]/norb
nspin = weights.shape[-1]
ndim = weights.shape[-2]
try:
out = open(fname, 'w')
except:
post_error('Unable to open "{0}" for writing'.format(fname))
# Write the first line of the PROCAR file
if phases is not None:
out.write('PROCAR lm decomposed + phase\n')
else:
out.write('PROCAR lm decomposed\n')
# Format out the column title line for orbital weights
orb_ttl_1 = 'ion '
orb_ttl_2 = 'ion '
for i in xrange(norb):
orb_ttl_1 += '{0: >6} '.format(orblabels[i])
orb_ttl_2 += '{0: >6} '.format(orblabels[i])
orb_ttl_1 += '{0: >6}\n'.format('tot')
orb_ttl_2 += '\n'
for s in xrange(nspin):
# Write the second line containing the sizes
out.write('# of k-points: {0} # of bands: {1}'
' # of ions: {2}\n\n'.format(npoints, nbands, nions))
for i, k in enumerate(kpoints):
# Write the k-point info
out.write(' k-point {0: >4} : '.format(i+1))
out.write('{0:.8f} {1:.8f} {2:.8f} '.format(*k))
out.write('weight = {0:.8f}\n\n'.format(kweights[i]))
for j, b in enumerate(bands[i,:,s]):
# Write the band info
out.write('band {0: >4} # '.format(j+1))
out.write('energy {0: >13.8f} # '.format(b))
out.write('occ. {0: >11.8f}\n\n'.format(occupations[i, j, s]))
# Write absolute weight blocks. In case of
# non-collinear calculation, there is four
# such blocks
for d in xrange(ndim):
if d == 0:
# Write names of orbitals (s, px, py etc...)
out.write(orb_ttl_1)
# Allocate storage for accumulation of orbital totals
tot_orb = np.zeros(norb, float)
# Loop over individual atoms
for k in xrange(nions):
# Write atom's index
out.write('{0: >3} '.format(k+1))
# Extract corresponding weights
w = weights[i, k*norb:(k+1)*norb, j,d,s]
# Add to totals
tot_orb += w
# Write out row of weights
for l in xrange(norb):
out.write('{0: >6.3f} '.format(w[l]))
# Write atom total
out.write('{0: >6.3f}\n'.format(np.sum(w)))
# We will now write line with orbital totals
out.write('tot ')
for l in xrange(norb):
out.write('{0: >6.3f} '.format(tot_orb[l]))
# Finally, atom+orbital total
out.write('{0: >6.3f}\n'.format(np.sum(tot_orb)))
# If we have phases we write them now
if phases is not None:
# Write again names of orbitals
out.write(orb_ttl_2)
# Loop over atoms
for k in xrange(nions):
# Write atom index
out.write('{0: >3} '.format(k+1))
# Extract corresponding phase
phs = phases[i, k*norb:(k+1)*norb, j, s]
# Write real part
for l in xrange(norb):
out.write('{0: >6.3f} '.format(phs[l].real))
# Write atom index
out.write('\n{0: >3} '.format(k+1))
# Write imaginary part
for l in xrange(norb):
out.write('{0: >6.3f} '.format(phs[l].imag))
out.write('\n')
out.write('\n')
out.write('\n')
out.close()
def parse_procar(filename):
'''This function parses a PROCAR file. It returns a tuple
consisting of following elements:
orbitals - (norbs) string array of orbital labels (s, px, py etc...)
kpoints - (npoints,3) float array of k-point coordinates
kweights - (npoints) float array of k-point weights
bands - (npoints,nbands,nspin) float array of band energies
occupancies - (npoints,nbands,nspin) float array of band occupancies
weights - (npoints,nions*norbs,nbands,ndim,nspin) float array
of orbital weights
phases - (npoints,nions*norbs,nbands,nspin) complex array of
phases of orbital weights if LORBIT=12, otherwise None
Where:
norbs - number of orbitals (It can be 9 or 16 with f orbitals)
npoints - number of k-points
nbands - number of bands
nspin - number of spins (1 for non spin-polarized, 2 otherwise)
nions - number of atoms
ndim - orbital weight dimensionality (1 for collinear, 4 otherwise)
'''
try:
gl = Getlines(filename)
except:
post_error('Unable to open "{0}" for reading.'.format(filename))
header_1 = gl.get_next()
header_2 = gl.get_next().split()
npoints = int(header_2[3])
nbands = int(header_2[7])
nions = int(header_2[-1])
# Remember the position in file
start = gl.tell()
# Skip two lines containing first k-point and band
gl.get_next()
gl.get_next()
# Determine the number of orbitals
orbitals = gl.get_next().split()[1:-1]
norbs = len(orbitals)
# Allocate maximal storage. In case calculation was
# non spin-polarized or collinear we can just trim
# the excess components at the end
kpoints = np.zeros((npoints, 3), float)
kweights = np.zeros(npoints, float)
bands = np.zeros((npoints, nbands, 2), float)
occupancies = np.zeros((npoints, nbands, 2), float)
weights = np.zeros((npoints, nions * norbs, nbands, 4, 2), float)
dim = 0
# Determine if the calculation was non-collinear
# by counting how many lines in the first band
# block begin with tot. That number will be equal
# to the number of sub-blocks for orbital weights
# (1 in case of collinear and 4 otherwise)
while True:
line = gl.get_next()
if line.startswith('tot'):
dim += 1
elif line.startswith('band'):
break
# This function will read block of absolute weights
# for i-th k-point, j-th band and s-th spin component
def get_absweights(i, j, s):
# Skip line with orbital names
gl.get_next()
# k loops over total, mx, my and mz
for k in xrange(dim):
# l goes over ions
for l in xrange(nions):
weights[i,l*norbs:(l+1)*norbs,j,k,s] = \
np.array(gl.get_next().split()[1:-1], float)
# Skip line with totals
gl.get_next()
# Check whether phase information is included
if '+ phase' in header_1:
# Allocate storage for phases
phases = np.zeros((npoints, nions * norbs, nbands, 2), complex)
# Declare nested function that handles
# parsing of complex weights
def get_weights(i, j, s):
# Read abs values of weights
get_absweights(i, j, s)
# Skip line with orbital names
gl.get_next()
for k in xrange(nions):
# Get real part
phases[i,k*norbs:(k+1)*norbs,j,s] = \
np.array(gl.get_next().split()[1:], float)
# Get imaginary part
phases[i,k*norbs:(k+1)*norbs,j,s] += \
1j*np.array(gl.get_next().split()[1:], float)
else:
# Phases are None in this case
phases = None
# In this case we just have absolutes of weights
# No need for a new function
get_weights = get_absweights
# Go back to the beginning of the first k-point
gl.seek(start)
for i in xrange(npoints):
# Parse k-point coordinates
temp = gl.get_next()
problem_index = []
for ic in range(len(temp) - 1):
if temp[ic] <= '9' and temp[ic] >= '0' and temp[ic + 1] == '-':
problem_index.append(ic)
if len(problem_index):
addition = 0
for ic in problem_index:
temp = temp[:ic + 1 + addition] + ' ' + temp[ic + 1 +
addition:]
addition += 1
print temp
k_line = temp.split()
kpoints[i] = np.array(k_line[3:6], float)
kweights[i] = float(k_line[-1])
for j in xrange(nbands):
# Parse band energy
band_line = gl.get_next().split()
bands[i, j, 0] = float(band_line[4])
occupancies[i, j, 0] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 0)
# Seek now for the second spin component
res = gl.get_next(False)
# If there is no second spin component, finish by
# returning just the first component
if res is None:
# Trim the second spin component
bands = bands[:, :, :1]
occupancies = occupancies[:, :, :1]
weights = weights[:, :, :, :dim, :1]
if phases is not None:
phases = phases[:, :, :, :1]
return orbitals, kpoints, kweights, bands, occupancies, \
weights, phases
# Otherwise, read bands and weights for the second component
for i in xrange(npoints):
# Skip k-point coordinates
gl.get_next()
for j in xrange(nbands):
# Parse band energy
band_line = gl.get_next().split()
bands[i, j, 1] = float(band_line[4])
occupancies[i, j, 1] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 1)
return orbitals, kpoints, kweights, bands, occupancies, \
weights[:,:,:,:dim,:], phases
def write_procar(fname, orbitals, kpoints, kweights, bands, occupations,
weights, phases):
'''Write PROCAR file based on supplied data
'''
# Labels for orbitals
orblabels = [
's', 'py', 'pz', 'px', 'dxy', 'dyz', 'dz2', 'dxz', 'dx2', 'f-3', 'f-2',
'f-1', 'f0', 'f1', 'f2', 'f3'
]
norb = len(orbitals)
npoints = len(kpoints)
nbands = bands.shape[1]
nions = weights.shape[1] / norb
nspin = weights.shape[-1]
ndim = weights.shape[-2]
try:
out = open(fname, 'w')
except:
post_error('Unable to open "{0}" for writing'.format(fname))
# Write the first line of the PROCAR file
if phases is not None:
out.write('PROCAR lm decomposed + phase\n')
else:
out.write('PROCAR lm decomposed\n')
# Format out the column title line for orbital weights
orb_ttl_1 = 'ion '
orb_ttl_2 = 'ion '
for i in xrange(norb):
orb_ttl_1 += '{0: >6} '.format(orblabels[i])
orb_ttl_2 += '{0: >6} '.format(orblabels[i])
orb_ttl_1 += '{0: >6}\n'.format('tot')
orb_ttl_2 += '\n'
for s in xrange(nspin):
# Write the second line containing the sizes
out.write('# of k-points: {0} # of bands: {1}'
' # of ions: {2}\n\n'.format(
npoints, nbands, nions))
for i, k in enumerate(kpoints):
# Write the k-point info
out.write(' k-point {0: >4} : '.format(i + 1))
out.write('{0:.8f} {1:.8f} {2:.8f} '.format(*k))
out.write('weight = {0:.8f}\n\n'.format(kweights[i]))
for j, b in enumerate(bands[i, :, s]):
# Write the band info
out.write('band {0: >4} # '.format(j + 1))
out.write('energy {0: >13.8f} # '.format(b))
out.write('occ. {0: >11.8f}\n\n'.format(occupations[i, j, s]))
# Write absolute weight blocks. In case of
# non-collinear calculation, there is four
# such blocks
for d in xrange(ndim):
# Write names of orbitals (s, px, py etc...)
out.write(orb_ttl_1)
# Allocate storage for accumulation of orbital totals
tot_orb = np.zeros(norb, float)
# Loop over individual atoms
for k in xrange(nions):
# Write atom's index
out.write('{0: >3} '.format(k + 1))
# Extract corresponding weights
w = weights[i, k * norb:(k + 1) * norb, j, d, s]
# Add to totals
tot_orb += w
# Write out row of weights
for l in xrange(norb):
out.write('{0: >6.3f} '.format(w[l]))
# Write atom total
out.write('{0: >6.3f}\n'.format(np.sum(w)))
# We will now write line with orbital totals
out.write('tot ')
for l in xrange(norb):
out.write('{0: >6.3f} '.format(tot_orb[l]))
# Finally, atom+orbital total
out.write('{0: >6.3f}\n'.format(np.sum(tot_orb)))
# If we have phases we write them now
if phases is not None:
# Write again names of orbitals
out.write(orb_ttl_2)
# Loop over atoms
for k in xrange(nions):
# Write atom index
out.write('{0: >3} '.format(k + 1))
# Extract corresponding phase
phs = phases[i, k * norb:(k + 1) * norb, j, s]
# Write real part
for l in xrange(norb):
out.write('{0: >6.3f} '.format(phs[l].real))
# Write atom index
out.write('\n{0: >3} '.format(k + 1))
# Write imaginary part
for l in xrange(norb):
out.write('{0: >6.3f} '.format(phs[l].imag))
out.write('\n')
out.write('\n')
out.write('\n')
out.close()
def build_translations(tgens):
'''Build a list of translations and irreps from at most
three linearly independent generators specified as lists
of three fractions.
'''
if len(tgens) > 3:
post_error('There can be at most three generators '
'of fractional translations.')
# Use folded generators as floats to perform linear independece tests
tgensf = np.array(tgens, dtype=float) % 1
# Tolerance for linear independenec per dimension
eps = 1e-2
# Check if generators are linearly independent
if len(tgens) == 2 and np.all(np.cross(tgensf[0], tgensf[1]) < eps**2):
post_error('Generators are not linearly independant.')
elif len(tgens) == 3 and np.linalg.det(np.array(tgensf)) < eps**3:
post_error('Generators are not linearly independant.')
# Expand the generator list to be a 3x3 matrix
tgens = np.append(tgens, np.ones((3 - len(tgens), 3)), axis=0)
# Get the order of every generator
order = np.array([frac_translation_order(g) for g in tgens], int)
# Get the corresponding roots of unity which will be
# used to construct irreps
deltag = np.exp(-2 * np.pi * 1j / order)
# Fold the translation vectors into the unit cell
tgens = tgens % 1
# Total number of translations
ntrans = np.prod(order)
# Storage for translations
trans = np.zeros((ntrans, 3), float)
# Calculate irreps of every generator
irrepg = np.zeros((ntrans, 3), complex)
# Loop over all possible products of powers of generators
# and store the irreps
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ii = i * order[1] * order[2] + j * order[2] + k
irrepg[ii] = deltag**[i, j, k]
# Irrep table for all translations
irreps = np.zeros((ntrans, ntrans), complex)
# Loop over all posible products of powers of generators
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ti = i * order[1] * order[2] + j * order[2] + k
# Get the translation vector
trans[ti] = np.dot([i, j, k], tgens) % 1
# Get all irreps of that translations
for l in xrange(ntrans):
irreps[l, ti] = np.prod(irrepg[l]**[i, j, k])
return trans, irreps
def build_translations(tgens):
"""Build a list of translations and irreps from at most
three linearly independent generators specified in the
form [nx,ny,nz], representing translation [1/nx,1/ny,1/nz].
"""
if len(tgens) > 3:
post_error("There can be at most three generators " "of fractional translations.")
# Check if generators are linearly independent
if len(tgens) == 2 and np.all(np.cross(tgens[0], tgens[1]) == 0):
post_error("Generators are not linearly independant.")
elif len(tgens) == 3 and np.linalg.det(tgens) == 0:
post_error("Generators are not linearly independant.")
# Expand the generator list to have a 3x3 matrix
tgens = np.append(tgens, np.ones((3 - len(tgens), 3)), axis=0)
# Get the order of every generator
order = np.array([lcmm(*g) for g in tgens], int)
# Get the corresponding roots of unity which will be
# used to construct irreps
deltag = np.exp(-2 * np.pi * 1j / order)
# Calculate translation vectors
tgens = (1.0 / tgens) % 1
# Total number of translations
ntrans = np.prod(order)
# Storage for translations
trans = np.zeros((ntrans, 3), float)
# Calculate irreps of every generator
irrepg = np.zeros((ntrans, 3), complex)
# Loop over all possible products of powers of generators
# and store the irreps
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ii = i * order[1] * order[2] + j * order[2] + k
irrepg[ii] = deltag ** [i, j, k]
# Irrep table for all translations
irreps = np.zeros((ntrans, ntrans), complex)
# Loop over all posible products of powers of generators
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ti = i * order[1] * order[2] + j * order[2] + k
# Get the translation vector
trans[ti] = np.dot([i, j, k], tgens) % 1
# Get all irreps of that translations
for l in xrange(ntrans):
irreps[l, ti] = np.prod(irrepg[l] ** [i, j, k])
return trans, irreps
def parse_procar(filename):
'''This function parses a PROCAR file. It returns a tuple
consisting of following elements:
orbitals - (norbs) string array of orbital labels (s, px, py etc...)
kpoints - (npoints,3) float array of k-point coordinates
kweights - (npoints) float array of k-point weights
bands - (npoints,nbands,nspin) float array of band energies
occupancies - (npoints,nbands,nspin) float array of band occupancies
weights - (npoints,nions*norbs,nbands,ndim,nspin) float array
of orbital weights
phases - (npoints,nions*norbs,nbands,nspin) complex array of
phases of orbital weights if LORBIT=12, otherwise None
Where:
norbs - number of orbitals (It can be 9 or 16 with f orbitals)
npoints - number of k-points
nbands - number of bands
nspin - number of spins (1 for non spin-polarized, 2 otherwise)
nions - number of atoms
ndim - orbital weight dimensionality (1 for collinear, 4 otherwise)
'''
try:
gl = Getlines(filename)
except:
post_error('Unable to open "{0}" for reading.'.format(filename))
header_1 = gl.readline()
header_2 = gl.readline().split()
npoints = int(header_2[3])
nbands = int(header_2[7])
nions = int(header_2[-1])
# Remember the position in file
start = gl.tell()
# Skip two lines containing first k-point and band
gl.readline()
gl.readline()
# Determine the number of orbitals
orbitals = gl.readline().split()[1:-1]
norbs = len(orbitals)
# Allocate maximal storage. In case calculation was
# non spin-polarized or collinear we can just trim
# the excess components at the end
kpoints = np.zeros((npoints, 3), float)
kweights = np.zeros(npoints, float)
bands = np.zeros((npoints, nbands, 2), float)
occupancies = np.zeros((npoints, nbands, 2), float)
weights = np.zeros((npoints, nions*norbs, nbands, 4, 2), float)
dim = 0
# Determine if the calculation was non-collinear
# by counting how many lines in the first band
# block begin with tot. That number will be equal
# to the number of sub-blocks for orbital weights
# (1 in case of collinear and 4 otherwise)
while True:
line = gl.readline()
if line.startswith('tot'):
dim += 1
elif line.startswith('band'):
break
# This function will read block of absolute weights
# for i-th k-point, j-th band and s-th spin component
def get_absweights(i, j, s):
# Skip line with orbital names
gl.readline()
for k in xrange(dim):
# Fetch entire orbital weight block
data = np.fromfile(gl, sep=" ", count=nions*(norbs+2))
# Cast it into tabular shape
data = data.reshape((nions, norbs+2))
# Discard first and last columns and store weights
weights[i,:,j,k,s] = data[:,1:-1].flatten()
# Skip line with the totals
gl.readline()
# Check whether phase information is included
if '+ phase' in header_1:
# Allocate storage for phases
phases = np.zeros((npoints, nions*norbs, nbands, 2), complex)
# Declare nested function that handles
# parsing of complex weights
def get_weights(i, j, s):
# Read abs values of weights
get_absweights(i, j, s)
# Skip line with orbital names
gl.readline()
# Fetch entire phase block
data = np.fromfile(gl, sep=" ", count=2*nions*(norbs+1))
# Cast it into tabular shape
data = data.reshape((2*nions, norbs+1))
# Discard first column and store real and imaginary
# parts respectively
phases[i,:,j,s] = data[::2,1:].flatten()
phases[i,:,j,s] += 1j*data[1::2,1:].flatten()
else:
# Phases are None in this case
phases = None
# In this case we just have absolutes of weights
# No need for a new function
get_weights = get_absweights
# Go back to the beginning of the first k-point
gl.seek(start)
for i in xrange(npoints):
# Parse k-point coordinates
k_line = gl.readline().split()
kpoints[i] = [float(k_line[c]) for c in [3, 4, 5]]
kweights[i] = float(k_line[-1])
for j in xrange(nbands):
# Parse band energy
band_line = gl.readline().split()
bands[i, j, 0] = float(band_line[4])
occupancies[i, j, 0] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 0)
# Seek now for the second spin component
res = gl.readline(False)
# If there is no second spin component, finish by
# returning just the first component
if res is None:
# Trim the second spin component
bands = bands[:,:,:1]
occupancies = occupancies[:,:,:1]
weights = weights[:,:,:,:dim,:1]
if phases is not None:
phases = phases[:,:,:,:1]
return [orbitals, kpoints, kweights, bands, occupancies, \
weights, phases]
# Otherwise, read bands and weights for the second component
for i in xrange(npoints):
# Skip k-point coordinates
gl.readline()
for j in xrange(nbands):
# Parse band energy
band_line = gl.readline().split()
bands[i, j, 1] = float(band_line[4])
occupancies[i, j, 1] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 1)
return [orbitals, kpoints, kweights, bands, occupancies, \
weights[:,:,:,:dim,:], phases]
def parse_poscar(filename):
'''Parses POSCAR file. Returns 3x3 float array
containing unit cell vectors as rows, Nx3
array containing fractional positions of atoms,
N being number of atoms and a list of chemical
symbols.
'''
try:
gl = Getlines(filename)
except:
post_error('Unable to open "{0}" for reading.'.format(filename))
# Skip the comment line
gl.readline()
# Read the scaling factor
f = float(gl.readline())
# Read the unit cell vectors
cell = np.zeros((3, 3), float)
cell[0] = f*np.array(gl.readline().split(), float)
cell[1] = f*np.array(gl.readline().split(), float)
cell[2] = f*np.array(gl.readline().split(), float)
# Read the chemical symbols
syms = gl.readline().split()
# Read the atom counts
counts = np.array(gl.readline().split(), int)
# Get the number of atoms
natoms = np.sum(counts)
# Rearrange into the long list of chemical symbols
symbols = []
for s, c in zip(syms, counts):
symbols += [s]*c
# Cartesian or fractional coordinates?
ctype = gl.readline()[0].lower()
if ctype == 'c':
mult = np.linalg.inv(cell)
elif ctype == 'd':
mult = np.eye(3)
else:
post_error('"{0}" is unknown POSCAR option'.format(plines[7].strip()))
# Allocate storage for positions
spos = np.zeros((len(symbols), 3))
# Read the positions
for i in xrange(len(symbols)):
spos[i] = np.array(gl.readline().split()[:3], float)
# If necessary, this will convert from
# Cartesian to fractional coordinates
spos = np.dot(spos, mult)
return cell, spos, symbols
def build_translations(tgens):
'''Build a list of translations and irreps from at most
three linearly independent generators specified as lists
of three fractions.
'''
if len(tgens) > 3:
post_error('There can be at most three generators '
'of fractional translations.')
# Use folded generators as floats to perform linear independece tests
tgensf = np.array(tgens, dtype=float)%1
# Tolerance for linear independenec per dimension
eps = 1e-2
# Check if generators are linearly independent
if len(tgens) == 2 and np.all(np.cross(tgensf[0], tgensf[1]) < eps**2):
post_error('Generators are not linearly independant.')
elif len(tgens) == 3 and np.linalg.det(np.array(tgensf)) < eps**3:
post_error('Generators are not linearly independant.')
# Expand the generator list to be a 3x3 matrix
tgens = np.append(tgens, np.ones((3-len(tgens), 3)), axis=0)
# Get the order of every generator
order = np.array([frac_translation_order(g) for g in tgens], int)
# Get the corresponding roots of unity which will be
# used to construct irreps
deltag = np.exp(-2*np.pi*1j/order)
# Fold the translation vectors into the unit cell
tgens = tgens % 1
# Total number of translations
ntrans = np.prod(order)
# Storage for translations
trans = np.zeros((ntrans, 3), float)
# Calculate irreps of every generator
irrepg = np.zeros((ntrans, 3), complex)
# Loop over all possible products of powers of generators
# and store the irreps
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ii = i*order[1]*order[2]+j*order[2]+k
irrepg[ii] = deltag**[i, j, k]
# Irrep table for all translations
irreps = np.zeros((ntrans, ntrans), complex)
# Loop over all posible products of powers of generators
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ti = i*order[1]*order[2]+j*order[2]+k
# Get the translation vector
trans[ti] = np.dot([i, j, k], tgens)%1
# Get all irreps of that translations
for l in xrange(ntrans):
irreps[l, ti] = np.prod(irrepg[l]**[i, j, k])
return trans, irreps
def build_translations(tgens):
'''Build a list of translations and irreps from at most
three linearly independent generators specified in the
form [nx,ny,nz], representing translation [1/nx,1/ny,1/nz].
'''
if len(tgens) > 3:
post_error('There can be at most three generators '
'of fractional translations.')
# Check if generators are linearly independent
if len(tgens) == 2 and np.all(np.cross(tgens[0], tgens[1]) == 0):
post_error('Generators are not linearly independant.')
elif len(tgens) == 3 and np.linalg.det(tgens) == 0:
post_error('Generators are not linearly independant.')
# Expand the generator list to have a 3x3 matrix
tgens = np.append(tgens, np.ones((3 - len(tgens), 3)), axis=0)
# Get the order of every generator
order = np.array([lcmm(*g) for g in tgens], int)
# Get the corresponding roots of unity which will be
# used to construct irreps
deltag = np.exp(-2 * np.pi * 1j / order)
# Calculate translation vectors
tgens = (1.0 / tgens) % 1
# Total number of translations
ntrans = np.prod(order)
# Storage for translations
trans = np.zeros((ntrans, 3), float)
# Calculate irreps of every generator
irrepg = np.zeros((ntrans, 3), complex)
# Loop over all possible products of powers of generators
# and store the irreps
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ii = i * order[1] * order[2] + j * order[2] + k
irrepg[ii] = deltag**[i, j, k]
# Irrep table for all translations
irreps = np.zeros((ntrans, ntrans), complex)
# Loop over all posible products of powers of generators
for i in xrange(order[0]):
for j in xrange(order[1]):
for k in xrange(order[2]):
ti = i * order[1] * order[2] + j * order[2] + k
# Get the translation vector
trans[ti] = np.dot([i, j, k], tgens) % 1
# Get all irreps of that translations
for l in xrange(ntrans):
irreps[l, ti] = np.prod(irrepg[l]**[i, j, k])
return trans, irreps
def parse_procar(filename):
'''This function parses a PROCAR file. It returns a tuple
consisting of following elements:
orbitals - (norbs) string array of orbital labels (s, px, py etc...)
kpoints - (npoints,3) float array of k-point coordinates
kweights - (npoints) float array of k-point weights
bands - (npoints,nbands,nspin) float array of band energies
occupancies - (npoints,nbands,nspin) float array of band occupancies
weights - (npoints,nions*norbs,nbands,ndim,nspin) float array
of orbital weights
phases - (npoints,nions*norbs,nbands,nspin) complex array of
phases of orbital weights if LORBIT=12, otherwise None
Where:
norbs - number of orbitals (It can be 9 or 16 with f orbitals)
npoints - number of k-points
nbands - number of bands
nspin - number of spins (1 for non spin-polarized, 2 otherwise)
nions - number of atoms
ndim - orbital weight dimensionality (1 for collinear, 4 otherwise)
'''
try:
gl = Getlines(filename)
except:
post_error('Unable to open "{0}" for reading.'.format(filename))
header_1 = gl.readline()
header_2 = gl.readline().split()
npoints = int(header_2[3])
nbands = int(header_2[7])
nions = int(header_2[-1])
# Remember the position in file
start = gl.tell()
# Skip two lines containing first k-point and band
gl.readline()
gl.readline()
# Determine the number of orbitals
orbitals = gl.readline().split()[1:-1]
norbs = len(orbitals)
# Allocate maximal storage. In case calculation was
# non spin-polarized or collinear we can just trim
# the excess components at the end
kpoints = np.zeros((npoints, 3), float)
kweights = np.zeros(npoints, float)
bands = np.zeros((npoints, nbands, 2), float)
occupancies = np.zeros((npoints, nbands, 2), float)
weights = np.zeros((npoints, nions * norbs, nbands, 4, 2), float)
dim = 0
# Determine if the calculation was non-collinear
# by counting how many lines in the first band
# block begin with tot. That number will be equal
# to the number of sub-blocks for orbital weights
# (1 in case of collinear and 4 otherwise)
while True:
line = gl.readline()
if line.startswith('tot'):
dim += 1
elif line.startswith('band'):
break
# This function will read block of absolute weights
# for i-th k-point, j-th band and s-th spin component
def get_absweights(i, j, s):
# Skip line with orbital names
gl.readline()
for k in xrange(dim):
# Fetch entire orbital weight block
data = np.fromfile(gl, sep=" ", count=nions * (norbs + 2))
# Cast it into tabular shape
data = data.reshape((nions, norbs + 2))
# Discard first and last columns and store weights
weights[i, :, j, k, s] = data[:, 1:-1].flatten()
# Skip line with the totals
gl.readline()
# Check whether phase information is included
if '+ phase' in header_1:
# Allocate storage for phases
phases = np.zeros((npoints, nions * norbs, nbands, 2), complex)
# Declare nested function that handles
# parsing of complex weights
def get_weights(i, j, s):
# Read abs values of weights
get_absweights(i, j, s)
# Skip line with orbital names
gl.readline()
# Fetch entire phase block
data = np.fromfile(gl, sep=" ", count=2 * nions * (norbs + 1))
# Cast it into tabular shape
data = data.reshape((2 * nions, norbs + 1))
# Discard first column and store real and imaginary
# parts respectively
phases[i, :, j, s] = data[::2, 1:].flatten()
phases[i, :, j, s] += 1j * data[1::2, 1:].flatten()
else:
# Phases are None in this case
phases = None
# In this case we just have absolutes of weights
# No need for a new function
get_weights = get_absweights
# Go back to the beginning of the first k-point
gl.seek(start)
for i in xrange(npoints):
# Parse k-point coordinates
k_line = gl.readline().split()
kpoints[i] = [float(k_line[c]) for c in [3, 4, 5]]
kweights[i] = float(k_line[-1])
for j in xrange(nbands):
# Parse band energy
band_line = gl.readline().split()
bands[i, j, 0] = float(band_line[4])
occupancies[i, j, 0] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 0)
# Seek now for the second spin component
res = gl.readline(False)
# If there is no second spin component, finish by
# returning just the first component
if res is None:
# Trim the second spin component
bands = bands[:, :, :1]
occupancies = occupancies[:, :, :1]
weights = weights[:, :, :, :dim, :1]
if phases is not None:
phases = phases[:, :, :, :1]
return [orbitals, kpoints, kweights, bands, occupancies, \
weights, phases]
# Otherwise, read bands and weights for the second component
for i in xrange(npoints):
# Skip k-point coordinates
gl.readline()
for j in xrange(nbands):
# Parse band energy
band_line = gl.readline().split()
bands[i, j, 1] = float(band_line[4])
occupancies[i, j, 1] = float(band_line[-1])
# Parse orbital weights
get_weights(i, j, 1)
return [orbitals, kpoints, kweights, bands, occupancies, \
weights[:,:,:,:dim,:], phases]
