public function getByPivot($pivot)
    {
        $result = [];
        foreach ($this->added as $entry) {
            if (!isset($entry[$pivot])) {
                throw new InvalidArgumentException("Invalid pivot given: '$pivot'.");
            }
            if (isset($result[$entry[$pivot]])) {
                $result[$entry[$pivot]]++;
            } else {
                $result[$entry[$pivot]] = 1;
            }
        }
        foreach ($this->removed as $entry) {
            if (!isset($entry[$pivot])) {
                throw new InvalidArgumentException("Invalid pivot given: '$pivot'.");
            }
            if (isset($result[$entry[$pivot]])) {
                $result[$entry[$pivot]]--;
                if ($result[$entry[$pivot]] === 0) {
                    unset($result[$entry[$pivot]]);
                }
            } else {
                $result[$entry[$pivot]] = -1;
            }
        }
        return $result;
    }
public function getByPivot($pivot)
    {
        $result = [];
        foreach ($this->added as $entry) {
            if (!isset($entry[$pivot])) {
                throw new InvalidArgumentException("Invalid pivot given: '$pivot'.");
            }
            if (isset($result[$entry[$pivot]])) {
                $result[$entry[$pivot]]++;
            } else {
                $result[$entry[$pivot]] = 1;
            }
        }
        foreach ($this->removed as $entry) {
            if (!isset($entry[$pivot])) {
                throw new InvalidArgumentException("Invalid pivot given: '$pivot'.");
            }
            if (isset($result[$entry[$pivot]])) {
                $result[$entry[$pivot]]--;
                if ($result[$entry[$pivot]] === 0) {
                    unset($result[$entry[$pivot]]);
                }
            } else {
                $result[$entry[$pivot]] = -1;
            }
        }
        return $result;
    }
public function getByPivot ( $ pivot ) { $ result = [ ] ; foreach ( $ this -> added as $ entry ) { if ( ! isset ( $ entry [ $ pivot ] ) ) { throw new InvalidArgumentException ( "Invalid pivot given: '$pivot'." ) ; } if ( isset ( $ result [ $ entry [ $ pivot ] ] ) ) { $ result [ $ entry [ $ pivot ] ] ++ ; } else { $ result [ $ entry [ $ pivot ] ] = 1 ; } } foreach ( $ this -> removed as $ entry ) { if ( ! isset ( $ entry [ $ pivot ] ) ) { throw new InvalidArgumentException ( "Invalid pivot given: '$pivot'." ) ; } if ( isset ( $ result [ $ entry [ $ pivot ] ] ) ) { $ result [ $ entry [ $ pivot ] ] -- ; if ( $ result [ $ entry [ $ pivot ] ] === 0 ) { unset ( $ result [ $ entry [ $ pivot ] ] ) ; } } else { $ result [ $ entry [ $ pivot ] ] = - 1 ; } } return $ result ; }
Gets differences by given pivot

@param mixed $pivot
@return array
@throws InvalidArgumentException
Gets differences by given pivot