ncarvversion: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/ncarvversion - from package: ncl

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/ncarvversion - from package: ncl-ncarg

You may install the required package with command apt-get install {package}

Error in other languages:
ncarvversion: bevel nie gevind nie
ncarvversion: comandă negăsită
ncarvversion: comando não encontrado
ncarvversion: commande introuvable
ncarvversion: command not found
ncarvversion: käsku ei ole
ncarvversion: không tìm thấy lệnh
ncarvversion: komanda nerasta
ncarvversion: Kommando nicht gefunden.
ncarvversion: kommandot finns inte
ncarvversion: komut yok
ncarvversion: nie znaleziono polecenia
ncarvversion: níor aimsíodh an t-ordú
ncarvversion: no se encontró la orden
ncarvversion: no s'ha trobat l'ordre
ncarvversion: opdracht niet gevonden
ncarvversion: parancs nem található
ncarvversion: perintah tidak ditemukan
ncarvversion: príkaz nenájdený
ncarvversion: příkaz nenalezen
ncarvversion: команда не найдена
ncarvversion: командата не е открита
ncarvversion: 命令找不到
ncarvversion: コマンドが見つかりません