scalasca: 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/lib64/mpich/bin/scalasca - from package: scalasca-mpich
/usr/lib64/openmpi/bin/scalasca - from package: scalasca-openmpi

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

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