grdproject: 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/grdproject - from package: GMT

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

On Debian possible default full paths are:

/usr/lib/gmt/bin/grdproject - from package: GMT

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

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