f2py: 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/f2py - from package: numpy-f2py

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

On Debian possible default full paths are:

/usr/bin/f2py - from package: python-numpy

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

Error in other languages:
f2py: bevel nie gevind nie
f2py: comandă negăsită
f2py: comando não encontrado
f2py: commande introuvable
f2py: command not found
f2py: käsku ei ole
f2py: không tìm thấy lệnh
f2py: komanda nerasta
f2py: Kommando nicht gefunden.
f2py: kommandot finns inte
f2py: komut yok
f2py: nie znaleziono polecenia
f2py: níor aimsíodh an t-ordú
f2py: no se encontró la orden
f2py: no s'ha trobat l'ordre
f2py: opdracht niet gevonden
f2py: parancs nem található
f2py: perintah tidak ditemukan
f2py: príkaz nenájdený
f2py: příkaz nenalezen
f2py: команда не найдена
f2py: командата не е открита
f2py: 命令找不到
f2py: コマンドが見つかりません