#!/bin/sh

###############################################################################
##
##  HIGH VERBOSITY EXAMPLE
##
###############################################################################

# run from directory where this script is
cd `echo $0 | sed 's/\(.*\)\/.*/\1/'` # extract pathname
EXAMPLE_DIR=`pwd`

# check whether echo has the -e option
if test "`echo -e`" = "-e" ; then ECHO=echo ; else ECHO="echo -e" ; fi

$ECHO
$ECHO "$EXAMPLE_DIR : starting"
$ECHO
$ECHO "This example shows how to calculate the phonon dispersion of monolayer"
$ECHO "boron nitride along the Gamma-M-K-Gamma path"
$ECHO

# set the needed environment variables
. ../../../environment_variables

# required executables and pseudopotentials
BIN_LIST="pw.x ph.x q2r.x matdyn.x plotband.x"
PSEUDO_LIST="B.pbe-n-kjpaw_psl.0.1.UPF N.pbe-n-kjpaw_psl.0.1.UPF"

$ECHO
$ECHO "  executables directory: $BIN_DIR"
$ECHO "  pseudo directory:      $PSEUDO_DIR"
$ECHO "  temporary directory:   $TMP_DIR"
$ECHO "  checking that needed directories and files exist...\c"

# check for directories
for DIR in "$BIN_DIR" "$PSEUDO_DIR" ; do
    if test ! -d $DIR ; then
        $ECHO
        $ECHO "ERROR: $DIR not existent or not a directory"
        $ECHO "Aborting"
        exit 1
    fi
done
for DIR in "$TMP_DIR" "$EXAMPLE_DIR/results" ; do
    if test ! -d $DIR ; then
        mkdir $DIR
    fi
done
cd $EXAMPLE_DIR/results

# check for executables
for FILE in $BIN_LIST ; do
    if test ! -x $BIN_DIR/$FILE ; then
        $ECHO
        $ECHO "ERROR: $BIN_DIR/$FILE not existent or not executable"
        $ECHO "Aborting"
        exit 1
    fi
done

# check for pseudopotentials
for FILE in $PSEUDO_LIST ; do
    if test ! -r $PSEUDO_DIR/$FILE ; then
       $ECHO
       $ECHO "Downloading $FILE to $PSEUDO_DIR...\c"
            $WGET $PSEUDO_DIR/$FILE $NETWORK_PSEUDO/$FILE 2> /dev/null
    fi
    if test $? != 0; then
        $ECHO
        $ECHO "ERROR: $PSEUDO_DIR/$FILE not existent or not readable"
        $ECHO "Aborting"
        exit 1
    fi
done
$ECHO " done"64611

# how to run executables
PW_COMMAND="$PARA_PREFIX $BIN_DIR/pw.x $PARA_POSTFIX"
PH_COMMAND="$PARA_PREFIX $BIN_DIR/ph.x $PARA_POSTFIX"
MATDYN_COMMAND="$PARA_PREFIX $BIN_DIR/matdyn.x $PARA_POSTFIX"
Q2R_COMMAND="$PARA_PREFIX $BIN_DIR/q2r.x $PARA_POSTFIX"
PLOTBAND_COMMAND="$BIN_DIR/plotband.x"
GP_COMMAND=`which gnuplot 2>/dev/null`
if [ "$GP_COMMAND" = "" ]; then
        $ECHO
        $ECHO "gnuplot not in PATH"
        $ECHO "Results will not be plotted"
fi
$ECHO
$ECHO "  running pw.x as: $PW_COMMAND"
$ECHO "  running ph.x as: $PH_COMMAND"
$ECHO "  running q2r.x as:    $Q2R_COMMAND"
$ECHO "  running matdyn.x as: $MATDYN_COMMAND"
$ECHO "  running plotband.x as: $PLOTBAND_COMMAND"
$ECHO "  running gnuplot as: $GP_COMMAND"
$ECHO

# clean TMP_DIR
$ECHO "  cleaning $TMP_DIR...\c"
rm -rf $TMP_DIR/bn*
rm -rf $TMP_DIR/_ph0/bn*
$ECHO "  done"
#
#  SCF at k-mesh good enough for phonons
#
cat > bn.scf.in << EOF
 &control
   calculation='scf'
   restart_mode='from_scratch',
   prefix='bn',
   pseudo_dir = '$PSEUDO_DIR/',
   outdir='$TMP_DIR/'
   wf_collect = .false.
 /
 &system
    ibrav=  4, celldm(1) =4.7419, celldm(3) =4.3, nat= 2, ntyp= 2,
    ecutwfc =55,
    ecutrho =440,
    occupations='fixed', 
    assume_isolated='2D', 
 /
 &electrons
    conv_thr =  1d-10
    mixing_beta = 0.7
 /
ATOMIC_SPECIES
B 10.81     B.pbe-n-kjpaw_psl.0.1.UPF
N 14.00674  N.pbe-n-kjpaw_psl.0.1.UPF
ATOMIC_POSITIONS (alat)
B        0.000000000   0.288675135   0.000000000
N        0.000000000  -0.288675135   0.000000000 
K_POINTS {automatic}
12 12 1  0 0 0
EOF
$ECHO "  running the scf calculation...\c"
$PW_COMMAND < bn.scf.in > bn.scf.out
check_failure $?
$ECHO "  done"
#
cat > bn.ph.disp.in << EOF
Phonon dispersions for BN
 &inputph
  tr2_ph=1.0d-15,
  prefix='bn',
  outdir='$TMP_DIR/',
  fildyn='bn.disp.dyn',
  ldisp=.true.
  nq1=8, nq2=8, nq3=1,
 /
EOF
$ECHO "  running the ph calculation...\c"
$PH_COMMAND < bn.ph.disp.in > bn.ph.disp.out
check_failure $?
$ECHO "  done"
#
cat > q2r.in << EOF
 &input
  zasr='simple',  fildyn='bn.disp.dyn', flfrc='bn881.fc', loto_2d=.true.,
 /
EOF
$ECHO "  running q2r...\c"
$Q2R_COMMAND < q2r.in > q2r.out
check_failure $?
$ECHO "  done"
#
cat > matdyn.in <<EOF
 &input
    asr='simple', 
    flfrc='bn881.fc', flfrq='bn.freq', q_in_band_form=.true., loto_2d=.true.,
 /
 4
  0.00000000 0.00000000 0.0   40
  0.33333333 0.57735027 0.0   20
  0.00000000 0.57735027 0.0   30
  0.00000000 0.00000000 0.0   1
EOF

$ECHO "  running matdyn to interpolate the dispersion...\c"
$MATDYN_COMMAND < matdyn.in > matdyn.out
check_failure $?
$ECHO "  done"

cat > plotband.in <<EOF
bn.freq
0 1650
freq.disp.plot
freq.disp.ps
0.0
50.0 0.0
EOF
#
$ECHO "  writing the phonon dispersions in freq.disp.plot...\c"
$PLOTBAND_COMMAND < plotband.in > /dev/null
check_failure $?
$ECHO " done"
#

if [ "$GP_COMMAND" = "" ]; then
    break
else
cat > gnuplot.tmp <<EOF
set encoding iso_8859_15
set terminal postscript enhanced solid color "Helvetica" 20
set output "al.dispersions.ps"
#
set key off

set xrange [0:1.577350] 
dim=1600
set yrange [0:dim]
set arrow from 1,0. to 1,dim nohead  lw 2
set arrow from 2,0. to 2,dim nohead  lw 2
set arrow from 1.5,0. to 1.5,dim nohead  lw 2
set arrow from 3.4142,0. to 3.4142,dim nohead  lw 2
set ylabel "frequency (cm^{-1})"
unset xtics
lpos=-15
set label "{/Symbol G}" at -0.05,lpos
set label "K" at 0.66666666,lpos
set label "M" at 1.00000,lpos
set label "{/Symbol G}" at 1.58,lpos 

plot "freq.disp.plot" u 1:2 w l lw 3
EOF
$ECHO "  creating the postscript file al.dispersion.ps...\c"
$GP_COMMAND gnuplot.tmp
check_failure $?
$ECHO " done"
fi

$ECHO
$ECHO "$EXAMPLE_DIR: done"
