minimum-weight: 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/lib/x86_64-linux-gnu/gap/pkg/guava/bin/minimum-weight - from package: gap-guava-bin

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

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