dzedit-gfortran: command not found

Have You tried accessing the binary with the full path?

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/dzedit-gfortran - from package: cernlib-packlib-gfortran

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