#!/bin/sh

# 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 use pw.x to calculate the DOS of Ni."

# set the needed environment variables
. ./environment_variables

# required executables and pseudopotentials
BIN_LIST="pw.x dos.x projwfc.x kvecs_FS.x bands_FS.x"
PSEUDO_LIST="NiUS.RRKJ3.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 "ERROR: $PSEUDO_DIR/$FILE not existent or not readable"
        $ECHO "Aborting"
        exit 1
    fi
done
$ECHO " done"

# how to run executables
PW_COMMAND="$PARA_PREFIX $BIN_DIR/pw.x $PARA_POSTFIX"
DOS_COMMAND="$PARA_PREFIX $BIN_DIR/dos.x $PARA_POSTFIX"
PROJWFC_COMMAND="$PARA_PREFIX $BIN_DIR/projwfc.x $PARA_POSTFIX"
KVECS_COMMAND="$BIN_DIR/kvecs_FS.x "
BANDS_COMMAND="$BIN_DIR/bands_FS.x "
$ECHO
$ECHO "  running pw.x as:      $PW_COMMAND"
$ECHO "  running dos.x as:     $DOS_COMMAND"
$ECHO "  running projwfc.x as: $PROJWFC_COMMAND"
$ECHO "  running kvecs_FS.x as:  $KVECS_COMMAND"
$ECHO "  running bands_FS.x as:  $BANDS_COMMAND"
$ECHO
 
# clean TMP_DIR
$ECHO "  cleaning $TMP_DIR...\c"
rm -rf $TMP_DIR/*
$ECHO " done"

# self-consistent calculation
cat > ni.scf.in << EOF
 &control
    calculation='scf'
    restart_mode='from_scratch',
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, celldm(1) =6.48, nat=1, ntyp=1,
    nspin = 2,  starting_magnetization(1)=0.7,
    ecutwfc = 24.0, ecutrho = 288.0,
    occupations='smearing', smearing='methfessel-paxton', degauss=0.02
 /
 &electrons
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS
  60
   0.0625000  0.0625000  0.0625000   1.00
   0.0625000  0.0625000  0.1875000   3.00
   0.0625000  0.0625000  0.3125000   3.00
   0.0625000  0.0625000  0.4375000   3.00
   0.0625000  0.0625000  0.5625000   3.00
   0.0625000  0.0625000  0.6875000   3.00
   0.0625000  0.0625000  0.8125000   3.00
   0.0625000  0.0625000  0.9375000   3.00
   0.0625000  0.1875000  0.1875000   3.00
   0.0625000  0.1875000  0.3125000   6.00
   0.0625000  0.1875000  0.4375000   6.00
   0.0625000  0.1875000  0.5625000   6.00
   0.0625000  0.1875000  0.6875000   6.00
   0.0625000  0.1875000  0.8125000   6.00
   0.0625000  0.1875000  0.9375000   6.00
   0.0625000  0.3125000  0.3125000   3.00
   0.0625000  0.3125000  0.4375000   6.00
   0.0625000  0.3125000  0.5625000   6.00
   0.0625000  0.3125000  0.6875000   6.00
   0.0625000  0.3125000  0.8125000   6.00
   0.0625000  0.3125000  0.9375000   6.00
   0.0625000  0.4375000  0.4375000   3.00
   0.0625000  0.4375000  0.5625000   6.00
   0.0625000  0.4375000  0.6875000   6.00
   0.0625000  0.4375000  0.8125000   6.00
   0.0625000  0.4375000  0.9375000   6.00
   0.0625000  0.5625000  0.5625000   3.00
   0.0625000  0.5625000  0.6875000   6.00
   0.0625000  0.5625000  0.8125000   6.00
   0.0625000  0.6875000  0.6875000   3.00
   0.0625000  0.6875000  0.8125000   6.00
   0.0625000  0.8125000  0.8125000   3.00
   0.1875000  0.1875000  0.1875000   1.00
   0.1875000  0.1875000  0.3125000   3.00
   0.1875000  0.1875000  0.4375000   3.00
   0.1875000  0.1875000  0.5625000   3.00
   0.1875000  0.1875000  0.6875000   3.00
   0.1875000  0.1875000  0.8125000   3.00
   0.1875000  0.3125000  0.3125000   3.00
   0.1875000  0.3125000  0.4375000   6.00
   0.1875000  0.3125000  0.5625000   6.00
   0.1875000  0.3125000  0.6875000   6.00
   0.1875000  0.3125000  0.8125000   6.00
   0.1875000  0.4375000  0.4375000   3.00
   0.1875000  0.4375000  0.5625000   6.00
   0.1875000  0.4375000  0.6875000   6.00
   0.1875000  0.4375000  0.8125000   6.00
   0.1875000  0.5625000  0.5625000   3.00
   0.1875000  0.5625000  0.6875000   6.00
   0.1875000  0.6875000  0.6875000   3.00
   0.3125000  0.3125000  0.3125000   1.00
   0.3125000  0.3125000  0.4375000   3.00
   0.3125000  0.3125000  0.5625000   3.00
   0.3125000  0.3125000  0.6875000   3.00
   0.3125000  0.4375000  0.4375000   3.00
   0.3125000  0.4375000  0.5625000   6.00
   0.3125000  0.4375000  0.6875000   6.00
   0.3125000  0.5625000  0.5625000   3.00
   0.4375000  0.4375000  0.4375000   1.00
   0.4375000  0.4375000  0.5625000   3.00
EOF
$ECHO "  running the scf calculation for Ni...\c"
$PW_COMMAND < ni.scf.in > ni.scf.out
$ECHO " done"

# DOS calculation for Ni
cat > ni.dos.in << EOF
 &control
    calculation='nscf'
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, celldm(1) =6.48, nat=1, ntyp=1,
    nspin = 2,  starting_magnetization(1)=0.7,
    ecutwfc = 24.0, ecutrho = 288.0, nbnd=8,
    occupations='tetrahedra'
 /
 &electrons
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS {automatic}
 12 12 12 0 0 0
EOF

cat > ni.dos2.in << EOF
 &inputpp
    outdir='$TMP_DIR/'
    prefix='ni'
    fildos='ni.dos',
    Emin=5.0, Emax=25.0, DeltaE=0.1
 /
EOF

$ECHO "  running DOS calculation for Ni...\c"
$PW_COMMAND < ni.dos.in > ni.dos.out
$DOS_COMMAND < ni.dos2.in > ni.dos2.out
$ECHO " done"

cat > ni.pdos.in << EOF
 &inputpp
    outdir='$TMP_DIR/'
    prefix='ni'
    Emin=5.0, Emax=25.0, DeltaE=0.1
    ngauss=1, degauss=0.02
 /
EOF
$ECHO "  running PDOS calculation for Ni...\c"
$PROJWFC_COMMAND < ni.pdos.in > ni.pdos.out
$ECHO " done"

$ECHO "  Fermi Surface plot Spin-Polarized case...\c"

# self-consistent calculation - Spin-Polarized (SP) case

cat > ni.scf_SP.in << EOF
 &control
    calculation='scf'
    restart_mode='from_scratch',
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, celldm(1) =6.48, nat=1, ntyp=1,
    ecutwfc = 24.0, ecutrho = 288.0,
    occupations='smearing', 
    smearing='methfessel-paxton', 
    degauss=0.02
    nspin=2, 
    starting_magnetization(1)=0.8
 /
 &electrons
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS {automatic}
 8 8 8 0 0 0 
EOF
$ECHO "  running the scf calculation  spin-polarization ... \c"
$PW_COMMAND < ni.scf_SP.in > ni.scf0.SP.out
$ECHO " done"

#
# prepare input file ni.fs_SP.in
#
Sysname='ni'
nabc=' 16 16 16 '
n_start=3
n_last=6
#
E_Fermi=`grep Fermi ni.scf0.SP.out | cut -c 26-36` 
a1=`grep 'b(1)' ni.scf.out | cut -c 24-54`
a2=`grep 'b(2)' ni.scf.out | cut -c 24-54`
a3=`grep 'b(3)' ni.scf.out | cut -c 24-54`

cat > kvecs_FS.in <<EOF
$a1
$a2
$a3
$nabc
$Sysname
EOF

$KVECS_COMMAND < kvecs_FS.in > kvecs_FS.out

cat > ni.fs_SP.in << EOF
 &control
    calculation='nscf'
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, 
    celldm(1) =6.48, 
    nat=1, 
    ntyp=1,
    ecutwfc = 24.0, 
    ecutrho = 288.0, 
    nbnd=8
    nspin=2, 
    starting_magnetization(1)=0.8
 /
 &electrons
    diagonalization='cg'
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS
EOF

cat  kvecs_$Sysname >> ni.fs_SP.in

# input file ni.fs.in ready
$ECHO "  running the Fermi Surface calculation ... \c"
$PW_COMMAND   < ni.fs_SP.in > ni.fs.SP.out 
$ECHO " done"

# prepare input data (input_FS, Bands.out) for bands_FS

mv ni.fs.SP.out Bands_SP.out

cat > input_FS <<EOF
$n_start  $n_last
$E_Fermi
$Sysname
$nabc
$a1
$a2
$a3
EOF

$BANDS_COMMAND <Bands_SP.out  > bands_fs.out
mv Bands_up.bxsf    $Sysname.fs_up.bxsf 
mv Bands_down.bxsf  $Sysname.fs_down.bxsf 

##################

$ECHO "  Fermi Surface plot Non-Spin-Polarized (NSP) case...\c"

# self-consistent calculation - Non-Spin-Polarised case

cat > ni.scf_NSP.in << EOF
 &control
    calculation='scf'
    restart_mode='from_scratch',
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, celldm(1) =6.48, nat=1, ntyp=1,
    ecutwfc = 24.0, ecutrho = 288.0,
    occupations='smearing', 
    smearing='methfessel-paxton', 
    degauss=0.02
 /
 &electrons
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS {automatic}
 8 8 8 0 0 0 
EOF
$ECHO "  running the scf calculation  non spin-polarized case ... \c"
$PW_COMMAND < ni.scf_NSP.in > ni.scf0.NSP.out
$ECHO " done"

#
# prepare input file ni.fs.in
#
Sysname='ni'
nabc=' 16 16 16 '
n_start=3
n_last=6
#
E_Fermi=`grep Fermi ni.scf0.NSP.out | cut -c 26-36` 
a1=`grep 'b(1)' ni.scf.out | cut -c 24-54`
a2=`grep 'b(2)' ni.scf.out | cut -c 24-54`
a3=`grep 'b(3)' ni.scf.out | cut -c 24-54`

cat > kvecs_FS.in <<EOF
$a1
$a2
$a3
$nabc
$Sysname
EOF

$KVECS_COMMAND < kvecs_FS.in > kvecs_FS.out

cat > ni.fs_NSP.in << EOF
 &control
    calculation='nscf'
    prefix='ni',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=2, 
    celldm(1) =6.48, 
    nat=1, 
    ntyp=1,
    ecutwfc = 24.0, 
    ecutrho = 288.0, 
    nbnd=8
 /
 &electrons
    diagonalization='cg'
    conv_thr = 1.0e-10
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69 NiUS.RRKJ3.UPF
ATOMIC_POSITIONS
 Ni 0.0 0.0 0.0
K_POINTS
EOF

cat  kvecs_$Sysname >> ni.fs_NSP.in

# input file ni.fs.in ready
$ECHO "  running the Fermi Surface calculation ... \c"
$PW_COMMAND   < ni.fs_NSP.in > ni.fs_NSP.out 
$ECHO " done"

# prepare input data (input_FS, Bands.out) for bands_FS

mv ni.fs_NSP.out Bands_NSP.out

cat > input_FS <<EOF
$n_start  $n_last
$E_Fermi
$Sysname
$nabc
$a1
$a2
$a3
EOF

$BANDS_COMMAND < Bands_NSP.out > bands_fs.out
mv Bands.bxsf  ni.fs_NSP.bxsf 

$ECHO "  Fermi surface plot: use 'xcrysden --bxsf ni.fs_NSP.bxsf' to plot ...\c"
$ECHO " done"

$ECHO
$ECHO "$EXAMPLE_DIR: done"