[Bash] manipulate variables from different netcdf files using nco

#!/bin/bash # compute the toal precipitation (L+S) # usage: #           getTotalPrec.sh RainFile SnowFile #    assuming the variable name for rain  : pr #                                                 snow : prsn #copyright @ http://scriptdemo.blogspot.com ncVarNameRain="pr" ncVarNameSnow="prsn" if [ $# -eq 2 ]; then    RainFile=$1; SnowFile=$2 else    sed -n '3,6p' getTotalPrec.sh    exit fi [ ! -e ${RainFile} ] && echo "${RainFile} does not exist!" && exit [ ! -e ${SnowFile} ] && echo "${SnowFile} does not exist!" && exit oriP="ori_${RainFile}" cp ${RainFile} ${oriP} eval "ncks -A -v ${ncVarNameSnow} ${SnowFile} ${oriP}" eval "ncap2 -s 'prtot=${ncVarNameRain}+${ncVarNameSnow}' ${oriP} new${oriP}" ncks -v prtot new${oriP} total_${oriP} && rm -f new${oriP} eval "ncrename -v prtot,${ncVarNameRain} total_${oriP} && rm -f ${oriP}"