shell字符处理的几个函数

字符处理函数

#!/bin/bash# example:#    replacevariables func @x vara#        assume func=@x*@x+2*@x+1 vara=(a b c)#        to apply @x as a,b,c in func, the result is a*a+2*a+a b*b+2*b+1 c*c+2*c+1function replacevariables{    if [[ $# -ne 3 ]]; then        return ;    fi    local functionstr=$1    local var=$2    local appvararray    eval appvararray=(\${$3[@]})    local resultarray    local appvar    local i=0    for appvar in ${appvararray[@]}; do        resultarray[${i}]=`echo ${functionstr} | sed "s/${var}/${appvar}/g"`        ((i++))    done    echo ${resultarray[@]}}# example:#    combinearray vara varb ${hyphen}#        assume vara=(a b c) varb=(x y z) hyphen=+#        the result is a+x b+y c+zfunction combinearray{    if [[ $# -ne 3 ]]; then        return ;    fi    local vararray1    local vararray2    eval vararray1=(\${$1[@]})    eval vararray2=(\${$2[@]})    local hyphen=$3    local resultarray    local length    ((length=(${#vararray1[@]}<${#vararray2[@]}?${#vararray1[@]}:${#vararray2[@]})))    local i    for ((i=0;i<${length};i++)) ; do        eval resultarray[${i}]=\${vararray1[${i}]}${hyphen}\${vararray2[${i}]}    done    echo ${resultarray[@]}}# example:#    arraytostring vara hyphen#        assume vara=(a b c) hyphen=+#        the return result is a+b+cfunction arraytostring{    if [[ $# -ne 2 ]]; then        return ;    fi    local vararray    eval vararray=(\${$1[@]})    local result=""    local hyphen=$2local temphyphen=""    local var    for var in ${vararray[@]} ; do        result=${result}${temphyphen}${var}        temphyphen=${hyphen}    done    echo ${result}}