pc-makegnuplot: 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/pc-makegnuplot - from package: probcons-extra

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

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