2d-slam-demo: 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/2d-slam-demo - from package: mrpt-apps

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

Error in other languages:
2d-slam-demo: bevel nie gevind nie
2d-slam-demo: comandă negăsită
2d-slam-demo: comando não encontrado
2d-slam-demo: commande introuvable
2d-slam-demo: command not found
2d-slam-demo: käsku ei ole
2d-slam-demo: không tìm thấy lệnh
2d-slam-demo: komanda nerasta
2d-slam-demo: Kommando nicht gefunden.
2d-slam-demo: kommandot finns inte
2d-slam-demo: komut yok
2d-slam-demo: nie znaleziono polecenia
2d-slam-demo: níor aimsíodh an t-ordú
2d-slam-demo: no se encontró la orden
2d-slam-demo: no s'ha trobat l'ordre
2d-slam-demo: opdracht niet gevonden
2d-slam-demo: parancs nem található
2d-slam-demo: perintah tidak ditemukan
2d-slam-demo: príkaz nenájdený
2d-slam-demo: příkaz nenalezen
2d-slam-demo: команда не найдена
2d-slam-demo: командата не е открита
2d-slam-demo: 命令找不到
2d-slam-demo: コマンドが見つかりません