pbmtomatrixorbital: 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/pbmtomatrixorbital - from package: netpbm-progs

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

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