grads: 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/grads - from package: grads

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

On Debian possible default full paths are:

/usr/bin/grads - from package: grads

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

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