pspolar: command not found

Have You tried accessing the binary with the full path?

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/pspolar - from package: GMT

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

On Debian possible default full paths are:

/usr/lib/gmt/bin/pspolar - from package: GMT

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