[URGENT HELP]Severity: Notice Message: Undefined variable:user_id Filename: controllers/users.php

[eluser]chazy (aldever calvo)[/eluser]
hi.. i can't fix on what's happening on my CRUD in edit... this is my code it also says that i got error in line 63 and 65...

A PHP Error was encountered

Severity: Warning

Message: Missing argument 1 for Users::edit()

Filename: controllers/users.php

Line Number: 63

this is my code:

63: function edit($user_id)
64: {
65: $data['id'] = $this->user_model->GetUser(array('user_id' => $user_id));
66: if (!$data['id']) redirect('users');
67: }