#!/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
&files
  -p       ../NVTwat/wat.top
  -c       ../NVTwat/wat.rst
  -r       wat
  -o       wat
  -x       wat
  -f       wat
  -osf     .out
  -rsf     .rst
  -xsf     .trj
  -fsf     .frc
&end

&cntrl
  DoSETTLE = 1,
  DoRATTLE = 0,   Vdw14Fac = 2.0,   Elec14Fac = 1.2,
  ElecCut = 8.000,  vdw_cutoff = 8.000,
  dt = 1.0e-3,   nstlim = 50,  nfistep = 25,
  ntpr = 5,      ntwr = 5,     ntwf = 0,       ntwx = 0,
  ntt  = 1,
  temp0 = 300.0,
  SplnSpc = 0.015625,

  % Constant-pressure dynamics maintained by a Monte-Carlo barostat
  ntp      = 1,
  barostat = 2,
  mcbfrq   = 5,
  mcbtemp  = 300.0,
  mccomp   = 2.0e-3,
&end

&ewald
  vdwmeth = 0,
  dsum_tol = 1.0e-5,
  ordr1 = 4,
  ordr2 = 4,
  ordr3 = 4,
&end
EOF

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

# Analyze the relevant output
echo "% Volume energy" > vol.dat
for I in  0 1 ; do
  grep "^ .*Volume:" wat${I}.out >> vol.dat
done

${AMBERHOME}/AmberTools/test/dacdif vol.dat.save vol.dat
/bin/rm -f mdgx.in wat[0-1].rst wat[0-1].out