qucsedit: 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/qucsedit - from package: qucs

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

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