下面是处理VASP输出数据得到态密度的脚本文件split_dos,与它配合的vp没有贴出来。学习vasp如果会一些shell编程，对vasp的运用会更灵活方便。这个程序听说比较老，有些问题，不能直接用来处理vasp4.6及以上版本的数据，也不能处理f电子。有兴趣的可以关注一下，看看语法本身，或者提出修改意见，都有BB鼓励。
:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D


#!/bin/ksh


# Script to break the VASP DOSCAR file into segments for
# each atomic site.
# JMS NRL 5/0/02

# Modified to also align the Fermi level from the ground state
# to E=0.0
# JMS NRL 6/19/02


# Executables reside here
BIN=~/bin                      #把这里修改为vp保存的路径。然后把split_dos的路径添加到PATH中。


if [ $# -ne 0 ]; then       #直接在shell提示符下输入split_dos运行，否则提醒Usage: split_dos,返回信息2.
        echo "Usage: split_dos"
        exit 2
fi

# Script to split the DOSCAR file into the atomic
# projections labeled by atom number
dosfile=DOSCAR
outfile=OUTCAR
infile=INCAR


# Token for splitting the files
token=$(sed -n '6 p' $dosfile | awk '{print $1}')   #这个token后面好像没有用到，有什么用呢？

# Number of points
nl=$(sed -n '6 p' $dosfile | awk '{print $3}')

# Number of atoms
natom=$(sed -n '1 p' $dosfile | awk '{print $1}')


# Get the Fermi level if the OUTCAR file is present,
# else we set it to zero.
if [ -a $outfile ]; then
    echo "The" $outfile "exists, we use it to get the Fermi level,"
    echo "the RWIGS tag and the number of spins."
    efermi=$(grep "E-fermi" $outfile | tail -1 | awk '{print $3}')
    echo "Fermi level:" $efermi
    nspin=$(grep "ISPIN" $outfile | tail -1 | awk '{print $3}')
    if [ $nspin -eq 2 ]; then
        echo "Spin polarized calculation"
    else
        echo "Unpolarized calculation"
    fi

# 2.a
# JMS 2/3/03 Modified to accept specification by LORBIT token.
#
    lorbit=$(grep "LORBIT" $outfile | tail -1 | awk '{print $3}')
    if [ $lorbit -ge 10 ]; then
        echo "LORBIT > 10"
        echo "WARNING: not completely test for vasp.4.*"
        echo "Use at your own risk. Please check results for consistency."
        form=1
    else
# 2.a
        rwigs=$(grep "RWIGS" $outfile | tail -1 | awk '{print $3}' | sed 's/\.//g')
        if [ $rwigs -eq -100 ]; then
            echo "RWIGS token not set"
            form=0
        else
            echo "RWIGS token set"
            form=1
        fi
# 2.a
    fi
# 2.a

else
    echo "The" $outfile "does not exist, we set the Fermi level to 0"
    echo "assume an unpolarized calculation, and RWIGS not set"
    form=0
    nspin=1
    efermi=0.0
fi

# If the outcar file is not present and you wish to set something by hand
# you should do it here. Uncomment the tokens below and set them by hand.

#efermi=2.255
#form=
#nspin=

# Get the atomic coordinates
$BIN/vp >| tmp.dat
tail -$natom tmp.dat | awk '{printf "%s .8f .8f .8f \n", "#", $2, $3, $4}' >| tmp.dat2

# Total is first DOS
if [ $form -eq 0 ]; then   #这个很怪，为什么不直接i=0呢？
i=0
else
i=0
fi               

start=7
end=$((start+nl-1))
#echo $start $end
#exit 0
rm -f DOS0
if [ $form -eq 1 ]; then

    while [ $i -le $natom ]; do

            #echo $i $start $end

        if [ $i -gt 0 ]; then
            sed -n ''$i' p' tmp.dat2 >| DOS$i #读入对应原子位置坐标到DOSi第一行
        fi

        if [ $i -gt 0 ]; then

# Atomic projected DOS
            if [ $nspin -eq 2 ]; then
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, -1*$3, $4, -1*$5, $6, -1*$7}' >> DOS$i
            else
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, $3, $4 }' >> DOS$i
            fi               

        else

# Total DOS
            if [ $nspin -eq 2 ]; then
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, -1*$3, $4, -1*$5 }' >> DOS$i
            else
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f \n", $1+(-1)*'$efermi', $2, $3 }' >> DOS$i
            fi

        fi

        start=$((end+2))
        end=$((start+nl-1))
        i=$((i+1))
    done

else

    while [ $i -le 0 ]; do    #这个奇怪，为什么要讨论i<0呢？不是只需考虑i>=0吗？前面已经全部包含了的呀？

            #echo $i $start $end

        if [ $i -gt 0 ]; then
            sed -n ''$i' p' tmp.dat2 >| DOS$i
        fi

        if [ $i -gt 0 ]; then

# Atomic projected DOS
            if [ $nspin -eq 2 ]; then
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, -1*$3, $4, -1*$5, $6, -1*$7}' >> DOS$i
            else
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, $3, $4 }' >> DOS$i
            fi               

        else

# Total DOS
            if [ $nspin -eq 2 ]; then
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f .8f .8f \n", $1+(-1)*'$efermi', $2, -1*$3, $4, -1*$5 }' >> DOS$i
            else
                sed -n ''$start','$end' p' $dosfile | awk '{printf ".8f .8f .8f \n", $1+(-1)*'$efermi', $2, $3 }' >> DOS$i
            fi

        fi

        start=$((end+2))
        end=$((start+nl-1))
        i=$((i+1))
    done

fi

exit 0