[SOLVED] "Call to member function on non-object" error in CodeIgniter when referring to model name in lowercase

"Call to member function on non-object" error in CodeIgniter when referring to model name in lowercase

Could somebody please explain to me why I am receiving the below error, I have received it many times before and have not found out why:

Fatal error: Call to a member function category_exists() on a non-object in C:\wamp\www\application\controllers\news.php on line 50

The controller (news.php):

public function category($category, $id, $title)
{
    if ($this->news_model->category_exists($category) == true) {
        echo 'true';
    } else {
        echo 'false';
    }
}

The model:

public function category_exists($category)
{
    $this->db->where('news_category', $category);
    $query = $this->db->get('news_category');
    if ($query->num_rows() > 0) {
        return true;
    } else{
        return false;
    }
}

If you could explain what the error means and why it is a non-object or how to turn it into an object that would be great.

EDIT: MODEL IS AUTOLOADED

Solution

Copied to answer:

I may be off, but aren't model names case sensitive? So if your model is class News_model it should be called by $this->News_model->category_exists. (though you have omitted the declaration, so this is only a guess)