#!/bin/bash

# Check the existence of a test version of the mdgx program
MDGX="${AMBERHOME}/bin/mdgx"
if [ -n "${TESTmdgx}" ] ; then
  MDGX=${TESTmdgx}
  echo "MDGX set to ${MDGX}"
fi

# Write a simple input file
cat > mdgx.in << EOF
% This input will test the function of the SETTLE routines in mdgx by
% simulating a box of TIP4P water molecules for 30 steps.
&files
  -p       wat288.top
  -c       wat288Init.crd
  -r       wat288t
  -o       wat288t
  -osf     .out
  -rsf     .rst
&end

&cntrl

  % This is the flag that will activate SETTLE
  DoSETTLE = 1,

  % Factors concerning treatment of nonbonded interactions
  SplnSpc    =  0.015625,
  Vdw14Fac   =  2.0,
  Elec14Fac  =  1.2,
  es_cutoff  = 9.000,
  vdw_cutoff = 9.000,

  % Run mode is standard MD, time step 2fs
  RunMode = 0,
  dt = 2.0e-3,

  % Factors concerning the output rate; a total of three files for output
  % diagnostics, restarts, forces, and trajectory will be written in .crd and
  % .rst formats.
  nstlim =  30,
  ntpr = 5,
  ntwr = 30,
  ntwf = 0,
  ntwx = 0,

  % Thermostat control: dynamics at 300K, with initial temperature 300K,
  % as maintained by a Berendsen thermostat
  ntt = 1,
  tempi = 300.0,
  temp0 = 300.0,

  % Barostat control: NPT dynamics as maintained by a Monte-Carlo barostat
  ntp = 1,
  barostat = 2,
  mccomp = 2.0e-3,
  mcbfrq = 5,
&end

&ewald
  dsum_tol = 5.0e-6,
  ordr1 = 4,
  ordr2 = 4,
  ordr3 = 4,
  nfft1 = 24,
  nfft2 = 24,
  nfft3 = 24,
&end
EOF

# Run the mdgx program
${MDGX} -O -i mdgx.in

# Analyze the relevant output
echo "% Temperatures" > temperature.dat
grep "^ Temperature:" wat288t.out >> temperature.dat

${AMBERHOME}/AmberTools/test/dacdif temperature.dat.save temperature.dat
/bin/rm -f mdgx.in wat288t.rst wat288t.out