$this->input->post() data and "undefined index"

[eluser]CroNiX[/eluser]
The problem is probably in your search_lib::process_array_input().

$this->input->post('subject') will be an array of all the checked "subject" checkbox values.

So, it will look something like:

Code:

array(
  0 => 'Aging',
  1 => 'Agriculture and Food',
  2 => 'Women'
)

If only the first 2 and very last checkboxes were checked.