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LPP/scripts/distance.py
ckloss 80592c0da1 Committer: ckloss <ckloss@fluid38.(none)>
On branch master
 Initial commit for lpp, version 2011-10-11
2012-02-03 14:10:31 +01:00

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1.9 KiB
Python

#!/usr/bin/python
# Script: distance.py
# Purpose: check if any atom pairs are closer than specified distance
# Syntax: distance.py maxcut dump.file1 dump.file2 ...
# maxcut = flag atoms which are less than this distance apart
# Example: distance.py 0.95 dump.file1
# Author: Paul Crozier (Sandia)
# print out 2 atoms less than maxcut apart (with PBC)
from math import sqrt
if len(argv) < 3:
raise StandardError,"distance.py maxcut dump.file1 dump.file2 ..."
maxcut = float(argv[1])
maxcut_sq = maxcut*maxcut
files = ' '.join(argv[2:]) # dump files
d = dump(files,0)
d.map(1,"id",2,"type",3,"x",4,"y",5,"z")
while 1:
time = d.next()
if time < 0: break
d.unscale(time)
box = (d.snaps[-1].xlo,d.snaps[-1].ylo,d.snaps[-1].zlo,
d.snaps[-1].xhi,d.snaps[-1].yhi,d.snaps[-1].zhi)
d.aselect.all(time)
id,type,x,y,z = d.vecs(time,"id","type","x","y","z")
n = len(x)
xprd = box[3] - box[0]
yprd = box[4] - box[1]
zprd = box[5] - box[2]
for i in xrange(n):
for j in xrange(i+1,n):
delx = x[j] - x[i]
if abs(delx) > 0.5*xprd:
if delx < 0.0:
delx += xprd
else:
delx -= xprd
if (delx*delx < maxcut_sq):
dely = y[j] - y[i]
if abs(dely) > 0.5*yprd:
if dely < 0.0:
dely += yprd
else:
dely -= yprd
if ((dely*dely + delx*delx) < maxcut_sq):
delz = z[j] - z[i]
if abs(delz) > 0.5*zprd:
if delz < 0.0:
delz += zprd
else:
delz -= zprd
rsq = delx*delx + dely*dely + delz*delz
if rsq < maxcut_sq:
print "time = %d, id[i] = %d, id[j] = %d," \
" type[i] = %d, type[j] = %d, distance = %g" % \
(time, id[i], id[j], type[i], type[j], sqrt(rsq))
d.tselect.none()
d.tselect.one(time)
print "timestep = ", time
d.delete()