atlas_convert: 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/atlas_convert - from package: libatlas-cpp-0.6-dev

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

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