How to Fix/Clean Lambda warnings/errors from Views PHP
Before try to explode/implode  check that data exist in them 
as example  

"$price_loop1"   
 if($price_loop1) 
     $prices_number_of_person= implode(",", $price_loop1);


and for explode

  if($prices_number_of_person)
      $split_prices_number_of_person = explode(",", $prices_number_of_person);