Question

Is it possible to define the following data sructure in PHP?

typedef struct
{
  int maxrank;          
  float rankrat[maxpop];
  int rankno[maxpop]; 
  individual ind[maxpop],
    *ind_ptr; 
}population ; 

population pop;

Answer 1

You can’t define a data structure other than a class in PHP, so you can always do that. It would look a little something like this:

class Population
{
    public $maxrank;
    public $rankrat = array();
    public $rankno = array();
    public $ind = array();
    public $ind_ptr;
}

$population = new Population();

Looking a bit more at the data structure, you’d also want an Individual class, which would be referenced from $population->ind_ptr and $population->ind[]. Just remember, PHP is loosely typed, so your $ind_ptr can just as well become an array, string or whatever else instantly. A quick way around this would be with a type-hinted setter method (and subsequent getter) like this:

protected $_ind_ptr;
public function setIndPtr(Individual $ind)
{
    $this->_ind_ptr = $ind;
}
public function getIndPtr()
{
    return $this->_ind_ptr;
}

Alternatively, use an array to define it if it’s only in one location.