I don't know how to send the parameters $x and $y to the function
I want to compare the array with this function two dimensions

$products1 = array(array('TIR','Tires','100'),
                array('OIL','Oil','10'),
                array('SPK','Spark Plugs',4)
                  );
function compare($x,$y){
      if($x[1] == $y[1]){
            return 0;
      }
      else if($x[1]<$y[1]){
            return -1;
      }
      else{
            return 1;
      }
}
usort($products1,'compare');
for($row1=0;$row1<3;$row1++){
      for($column1=0;$column1<3;$column1++){
      echo ' | '.$products1[$row1][$column1];
      }
      echo '<br/>';
}

bertrc I want to compare the array with this function two dimensions

usort() does that for you. Whether what you wrote would "work" may depend on your answer to Weedpacket's question. Right now you'd be sorting on the 2nd element of each sub-array (since they are zero-indexed). If possible, you might want to turn that into an associative array, so that you can be explicit in your code as to which field(s) to sort by. E.g.:

$products1 = array(
  array('id' => 'TIR', 'name' => 'Tires', 'value' => 100),
  array('id' => 'OIL', 'name' => 'Oil', 'value' => 10),
  array('id' => 'SPK', 'name' => 'Spark Plugs', 'value' => 4)
);

function compare_name($x, $y) {
  // just because I can, not that it's necessarily "better"
  // than using if/elseif/else -- just shorter:
  return(min(1, max(-1, ($x['name'] <=> $y['name']))));
}

function compare_value($x, $y) {
  return(min(1, max(-1, ($x['value'] <=> $y['value']))));
}

// sort by the name
usort($products1,'compare_name');
print_r($products1);

// sort by the value
usort($products1, 'compare_value');
print_r($products1);

    NogDog
    I remember this coming up before, but I'm pretty confident that the min/max clamping of <=> shouldn't be necessary; usort is supposed to handle arbitrary integer values (I've often written comparison functions that just return the result of a subtraction). (And if <=> evaluates to something else, that has to be considered a bug in the operator.)

      Weedpacket Cool...I just remembered sometime or other I proposed using <=> as an option, and someone said it's not guaranteed to work since it's not (supposedly) guaranteed to only return -1, 0, or 1. 🤷

        NogDog I think it was that way around; but as far as "work" goes, I think it would only be an issue if you only checked for {-1, 0, 1} instead of {<0, 0, >0}.

            Write a Reply...