ycompar: 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/ycompar - from package: patchy

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

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