Page MenuHomec4science

double-re-short.py
No OneTemporary

File Metadata

Created
Sun, Nov 3, 16:26

double-re-short.py

#!/usr/bin/env python2.7
import os, sys
from numpy import *
import numpy.random
### Runs replica exchange with gREM (fix grem) for unlimited number of replicas on a set number of processors. This script is inefficient, but necessary if wanting to run with hundreds of replicas on relatively few number of procs.
### read number of processors from the command line
nproc = int(sys.argv[1])
### path to simulation directory
path = os.getcwd()
### path to LAMMPS executable
lmp = sys.argv[2]
### LAMMPS input name
inp = sys.argv[3]
### define pressure for simulations (0 if const V)
pressure = 0
### some constants for gREM, must match with LAMMPS input file!
H = -30000
eta = -0.01
#kB = 0.000086173324 # eV (metal)
kB = 0.0019872 # kcal/mol (real)
### define lambdas - script assumes that there are already existing directories with all files necessary to run
lambdas=[400,405,410,415,420,425]
ll = len(lambdas)
### define number of exchanges
starting_ex = int(loadtxt("lastexchange"))
how_many_ex = 5
max_exchange = starting_ex+how_many_ex
### array with walkers
walker = loadtxt("lastwalker")
### initiate array with enthalpies
enthalpy = zeros(ll)
aver_enthalpy = zeros(ll)
for exchange in arange(starting_ex,max_exchange):
print "run", exchange
for l in range(ll):
#print "replica", l
os.chdir(path+"/%s" % lambdas[l])
#os.system("cp restart_file restart_file%d" % exchange)
if (nproc > 1):
os.system("mpirun -np %d " + lmp + " -in ../" + inp + " -var lambda %g -var eta %g -var enthalpy %g > output" % (nproc, lambdas[l], eta, H))
if (nproc == 1):
os.system(lmp + " -in ../" + inp + " -var lambda %g -var eta %g -var enthalpy %g > output" % (lambdas[l], eta, H))
os.system("grep -v '[a-zA-Z]' output | awk '{if(NF==6 && NR>19)print $0}' | awk '{print $3}' >ent")
enthalpy[l] = os.popen("tail -n 1 ent").read()
ee = loadtxt("ent")
aver_enthalpy[l] = mean(ee[-1])
# os.system("mv dump.dcd dump%d.dcd" % exchange)
os.system("mv log.lammps log%d.lammps" % exchange)
# os.system("rm output")
os.system("mv final_restart_file final_restart_file%d" % exchange)
os.system("mv ent ent%d" % exchange)
os.system("bzip2 log%d.lammps ent%d" % (exchange,exchange))
os.system("cp final_restart_file%d restart_file" % exchange)
### replicas will be exchanged based on enthalpy order, not replicas order (termostat order)
#entalpy_sorted_indices = enthalpy.argsort()
aver_entalpy_sorted_indices = aver_enthalpy.argsort()
### choose pair of replicas for exchange attempt based on enthalpy order
pp = random.random_integers(0,ll-2)
first = aver_entalpy_sorted_indices[pp]
second = aver_entalpy_sorted_indices[pp+1]
#if (first>second):
# tmp = first
# first = second
# second = tmp
print "pair1:", first, second
### calculate weights for exchange criterion
w1 = log(lambdas[first]+eta*(enthalpy[first]-1*H))
w2 = log(lambdas[first]+eta*(enthalpy[second]-1*H))
w3 = log(lambdas[second]+eta*(enthalpy[first]-1*H))
w4 = log(lambdas[second]+eta*(enthalpy[second]-1*H))
weight = (w4-w3+w1-w2)/eta/kB
### generate randon number for exchange criterion and calc its log
LOGRANDNUM = log(random.random())
### wyzeruj warunki
compare1 = 0
compare2 = 0
if (weight>0):
compare1 = 1
if (weight>LOGRANDNUM):
compare2 = 1
### exchange restart files if exchange condition is satisfied
if (compare1>0 or compare2>0):
print "exchange1 accepted for pair", first, second, lambdas[first], lambdas[second], "with compares as", compare1, compare2, "weight as", weight, "and lograndnum", LOGRANDNUM
os.system("cp %s/%s/final_restart_file%d %s/%s/restart_file" % (path,lambdas[first],exchange,path,lambdas[second]))
os.system("cp %s/%s/final_restart_file%d %s/%s/restart_file" % (path,lambdas[second],exchange,path,lambdas[first]))
### update walkers
tmp1=walker[first]
tmp2=walker[second]
walker[first]=tmp2
walker[second]=tmp1
else:
print "exchange1 not accepted for pair", first, second, lambdas[first], lambdas[second], "with compares as", compare1, compare2, "weight as", weight, "and lograndnum", LOGRANDNUM
### choose again pair of replicas for exchange attempt based on enthalpy order
### but make sure this pair is different than the first pair
if_different = 0
while if_different<1:
pp2 = random.random_integers(0,ll-2)
third = aver_entalpy_sorted_indices[pp2]
fourth = aver_entalpy_sorted_indices[pp2+1]
if (third!=first and third!=second and third!=aver_entalpy_sorted_indices[pp-1]):
if_different = 1
print "pair2:", third, fourth
### calculate weights for exchange criterion
w1 = log(lambdas[third]+eta*(enthalpy[third]-1*H))
w2 = log(lambdas[third]+eta*(enthalpy[fourth]-1*H))
w3 = log(lambdas[fourth]+eta*(enthalpy[third]-1*H))
w4 = log(lambdas[fourth]+eta*(enthalpy[fourth]-1*H))
weight = (w4-w3+w1-w2)/eta/kB
### generate randon number for exchange criterion and calc its log
LOGRANDNUM = log(random.random())
### wyzeruj warunki
compare1 = 0
compare2 = 0
if (weight>0):
compare1 = 1
if (weight>LOGRANDNUM):
compare2 = 1
### exchange restart files if exchange condition is satisfied
if (compare1>0 or compare2>0):
print "exchange2 accepted for pair", third, fourth, lambdas[third], lambdas[fourth], "with compares as", compare1, compare2, "weight as", weight, "and lograndnum", LOGRANDNUM
os.system("cp %s/%s/final_restart_file%d %s/%s/restart_file" % (path,lambdas[third],exchange,path,lambdas[fourth]))
os.system("cp %s/%s/final_restart_file%d %s/%s/restart_file" % (path,lambdas[fourth],exchange,path,lambdas[third]))
### update walkers
tmp1=walker[third]
tmp2=walker[fourth]
walker[third]=tmp2
walker[fourth]=tmp1
else:
print "exchange2 not accepted for pair", third, fourth, lambdas[third], lambdas[fourth], "with compares as", compare1, compare2, "weight as", weight, "and lograndnum", LOGRANDNUM
#print "walkers:", walker
print "".join(["%d " % x for x in walker])
sys.stdout.flush()
lastwalker = open(path + "/lastwalker", "w")
lastwalker.write("".join(["%d " % w for w in walker]))
lastwalker.close()
lastexchange = open(path + "/lastexchange", "w")
lastexchange.write("%d" % (exchange+1))
lastexchange.close()

Event Timeline