gnatmetric: 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 Debian possible default full paths are:

/usr/bin/gnatmetric - from package: asis-programs

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

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