Custom Helper Problem ?

$ci->session->set_userdata($ws_session_data);

I managed to fix the code, thanks. But introduces a new error:

A PHP Error was encountered
Severity: Notice
Message: Array to string conversion
Filename: apps / Runcode.php
Line Number: 36

backtrace:
File: /var/www/Dropbox/screens.dev/public_html/application/controllers/apps/Runcode.php
Line: 36
Function: _error_handler

File: /var/www/Dropbox/screens.dev/public_html/index.php
Line: 315
Function: require_once

array