pymca: 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/pymca - from package: pymca

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

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