transformix: 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/transformix - from package: elastix

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

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