DAMASK_EICMD/processing/pre/geom_grainGrowth.py

229 lines
12 KiB
Python
Executable File

#!/usr/bin/env python2.7
# -*- coding: UTF-8 no BOM -*-
import os,sys,math
import numpy as np
from optparse import OptionParser
from scipy import ndimage
import damask
scriptName = os.path.splitext(os.path.basename(__file__))[0]
scriptID = ' '.join([scriptName,damask.version])
#--------------------------------------------------------------------------------------------------
# MAIN
#--------------------------------------------------------------------------------------------------
parser = OptionParser(option_class=damask.extendableOption, usage='%prog [option(s)] [geomfile(s)]', description = """
Smoothens out interface roughness by simulated curvature flow.
This is achieved by the diffusion of each initially sharply bounded grain volume within the periodic domain
up to a given distance 'd' voxels.
The final geometry is assembled by selecting at each voxel that grain index for which the concentration remains largest.
""", version = scriptID)
parser.add_option('-d', '--distance',
dest = 'd',
type = 'float', metavar = 'float',
help = 'diffusion distance in voxels [%default]')
parser.add_option('-N', '--iterations',
dest = 'N',
type = 'int', metavar = 'int',
help = 'curvature flow iterations [%default]')
parser.add_option('-i', '--immutable',
action = 'extend', dest = 'immutable', metavar = '<int LIST>',
help = 'list of immutable microstructure indices')
parser.add_option('-r', '--renumber',
dest = 'renumber', action='store_true',
help = 'output consecutive microstructure indices')
parser.add_option('--ndimage',
dest = 'ndimage', action='store_true',
help = 'use ndimage.gaussian_filter in lieu of explicit FFT')
parser.set_defaults(d = 1,
N = 1,
immutable = [],
renumber = False,
ndimage = False,
)
(options, filenames) = parser.parse_args()
options.immutable = map(int,options.immutable)
getInterfaceEnergy = lambda A,B: (A*B != 0)*(A != B)*1.0 # 1.0 if A & B are distinct & nonzero, 0.0 otherwise
struc = ndimage.generate_binary_structure(3,1) # 3D von Neumann neighborhood
# --- loop over input files -----------------------------------------------------------------------
if filenames == []: filenames = [None]
for name in filenames:
try: table = damask.ASCIItable(name = name,
buffered = False,
labeled = False)
except: continue
damask.util.report(scriptName,name)
# --- interpret header ----------------------------------------------------------------------------
table.head_read()
info,extra_header = table.head_getGeom()
damask.util.croak(['grid a b c: {}'.format(' x '.join(map(str,info['grid']))),
'size x y z: {}'.format(' x '.join(map(str,info['size']))),
'origin x y z: {}'.format(' : '.join(map(str,info['origin']))),
'homogenization: {}'.format(info['homogenization']),
'microstructures: {}'.format(info['microstructures']),
])
errors = []
if np.any(info['grid'] < 1): errors.append('invalid grid a b c.')
if np.any(info['size'] <= 0.0): errors.append('invalid size x y z.')
if errors != []:
damask.util.croak(errors)
table.close(dismiss = True)
continue
# --- read data -----------------------------------------------------------------------------------
microstructure = np.tile(table.microstructure_read(info['grid']).reshape(info['grid'],order='F'),
np.where(info['grid'] == 1, 2,1)) # make one copy along dimensions with grid == 1
grid = np.array(microstructure.shape)
# --- initialize support data ---------------------------------------------------------------------
# store a copy the initial microstructure to find locations of immutable indices
microstructure_original = np.copy(microstructure)
if not options.ndimage:
X,Y,Z = np.mgrid[0:grid[0],0:grid[1],0:grid[2]]
# Calculates gaussian weights for simulating 3d diffusion
gauss = np.exp(-(X*X + Y*Y + Z*Z)/(2.0*options.d*options.d)) \
/math.pow(2.0*np.pi*options.d*options.d,(3.0 - np.count_nonzero(info['grid'] == 1))/2.)
gauss[:,:,:grid[2]/2:-1] = gauss[:,:,1:(grid[2]+1)/2] # trying to cope with uneven (odd) grid size
gauss[:,:grid[1]/2:-1,:] = gauss[:,1:(grid[1]+1)/2,:]
gauss[:grid[0]/2:-1,:,:] = gauss[1:(grid[0]+1)/2,:,:]
gauss = np.fft.rfftn(gauss)
for smoothIter in range(options.N):
interfaceEnergy = np.zeros(microstructure.shape)
for i in (-1,0,1):
for j in (-1,0,1):
for k in (-1,0,1):
# assign interfacial energy to all voxels that have a differing neighbor (in Moore neighborhood)
interfaceEnergy = np.maximum(interfaceEnergy,
getInterfaceEnergy(microstructure,np.roll(np.roll(np.roll(
microstructure,i,axis=0), j,axis=1), k,axis=2)))
# periodically extend interfacial energy array by half a grid size in positive and negative directions
periodic_interfaceEnergy = np.tile(interfaceEnergy,(3,3,3))[grid[0]/2:-grid[0]/2,
grid[1]/2:-grid[1]/2,
grid[2]/2:-grid[2]/2]
# transform bulk volume (i.e. where interfacial energy remained zero), store index of closest boundary voxel
index = ndimage.morphology.distance_transform_edt(periodic_interfaceEnergy == 0.,
return_distances = False,
return_indices = True)
# want array index of nearest voxel on periodically extended boundary
periodic_bulkEnergy = periodic_interfaceEnergy[index[0],
index[1],
index[2]].reshape(2*grid) # fill bulk with energy of nearest interface
if options.ndimage:
periodic_diffusedEnergy = ndimage.gaussian_filter(
np.where(ndimage.morphology.binary_dilation(periodic_interfaceEnergy > 0.,
structure = struc,
iterations = int(round(options.d*2.)), # fat boundary
),
periodic_bulkEnergy, # ...and zero everywhere else
0.),
sigma = options.d)
else:
diffusedEnergy = np.fft.irfftn(np.fft.rfftn(
np.where(
ndimage.morphology.binary_dilation(interfaceEnergy > 0.,
structure = struc,
iterations = int(round(options.d*2.))),# fat boundary
periodic_bulkEnergy[grid[0]/2:-grid[0]/2, # retain filled energy on fat boundary...
grid[1]/2:-grid[1]/2,
grid[2]/2:-grid[2]/2], # ...and zero everywhere else
0.))*gauss)
periodic_diffusedEnergy = np.tile(diffusedEnergy,(3,3,3))[grid[0]/2:-grid[0]/2,
grid[1]/2:-grid[1]/2,
grid[2]/2:-grid[2]/2] # periodically extend the smoothed bulk energy
# transform voxels close to interface region
index = ndimage.morphology.distance_transform_edt(periodic_diffusedEnergy >= 0.5*np.amax(periodic_diffusedEnergy),
return_distances = False,
return_indices = True) # want index of closest bulk grain
periodic_microstructure = np.tile(microstructure,(3,3,3))[grid[0]/2:-grid[0]/2,
grid[1]/2:-grid[1]/2,
grid[2]/2:-grid[2]/2] # periodically extend the microstructure
microstructure = periodic_microstructure[index[0],
index[1],
index[2]].reshape(2*grid)[grid[0]/2:-grid[0]/2,
grid[1]/2:-grid[1]/2,
grid[2]/2:-grid[2]/2] # extent grains into interface region
immutable = np.zeros(microstructure.shape, dtype=bool)
# find locations where immutable microstructures have been or are now
for micro in options.immutable:
immutable += np.logical_or(microstructure == micro, microstructure_original == micro)
# undo any changes involving immutable microstructures
microstructure = np.where(immutable, microstructure_original,microstructure)
# --- renumber to sequence 1...Ngrains if requested -----------------------------------------------
# http://stackoverflow.com/questions/10741346/np-frequency-counts-for-unique-values-in-an-array
if options.renumber:
newID = 0
for microstructureID,count in enumerate(np.bincount(microstructure.flatten())):
if count != 0:
newID += 1
microstructure = np.where(microstructure == microstructureID, newID, microstructure)
newInfo = {'microstructures': 0,}
newInfo['microstructures'] = microstructure.max()
# --- report --------------------------------------------------------------------------------------
remarks = []
if newInfo['microstructures'] != info['microstructures']:
remarks.append('--> microstructures: {}'.format(newInfo['microstructures']))
if remarks != []: damask.util.croak(remarks)
# --- write header --------------------------------------------------------------------------------
table.labels_clear()
table.info_clear()
table.info_append(extra_header+[
scriptID + ' ' + ' '.join(sys.argv[1:]),
"grid\ta {grid[0]}\tb {grid[1]}\tc {grid[2]}".format(grid=info['grid']),
"size\tx {size[0]}\ty {size[1]}\tz {size[2]}".format(size=info['size']),
"origin\tx {origin[0]}\ty {origin[1]}\tz {origin[2]}".format(origin=info['origin']),
"homogenization\t{homog}".format(homog=info['homogenization']),
"microstructures\t{microstructures}".format(microstructures=newInfo['microstructures']),
])
table.head_write()
# --- write microstructure information ------------------------------------------------------------
formatwidth = int(math.floor(math.log10(microstructure.max())+1))
table.data = microstructure[::1 if info['grid'][0]>1 else 2,
::1 if info['grid'][1]>1 else 2,
::1 if info['grid'][2]>1 else 2,].\
reshape((info['grid'][0],info['grid'][1]*info['grid'][2]),order='F').transpose()
table.data_writeArray('%{}i'.format(formatwidth),delimiter = ' ')
# --- output finalization --------------------------------------------------------------------------
table.close()